Excerpts from Clement of Rome (Bishop of Rome, 90-100), First Epistle of Clement to the Corinthians:
This letter marks a dramatic moment in the history of Christianity. For the first time, we find here an argument for dividing the Christian community between the 'clergy' and the 'laity.' The church is to be organized in terms of a strict order of superiors and subordinates. Even within the clergy, Clement insists on ranking each member, whether bishop, priest, or deacon, "in his own order": each must observe "the rules and commandments" of his position at all times (Elaine Pagels, The Gnostic Gospels, p. 41).

1: Because of our recent series of unexpected misfortunes and set-backs, my dear friends, we feel there has been some delay in turning our attention to the causes of dispute in your community. We refer particularly to the odious and unholy breach of unity among you, which is quite incompatible with God's chosen people, and which a few hot-headed and unruly individuals have inflamed to such a pitch that your venerable and illustrious name, so richly deserving of everyone's affection, has been brought into serious disrepute.
There was a time when nobody could spend a short while among you without noticing the excellence and constancy of your faith. Who ever failed to be impressed by your sober and selfless Christian piety, to tell of your generous spirit of hospitality, or to pay tribute to the wide range and soundness of your knowledge? It was your habit at all times to act without fear or favour, living by the laws of God and deferring with correctness to those who were set over you. Your elders were treated with the honour due to them; your young men were counselled to be soberly and seriously minded; your womenfolk were bidden to go about their duties in irreproachable devotion and purity of conscience, showing all proper affection to their husbands; they were taught to make obedience the rule of their lives, to manage their households decorously, and to be patterns of discretion in every way.

3: But when good repute and rising numbers were granted to you in full measure, the saying of Scripture came to pass: my beloved did eat and drink, he grew and waxed fat and kicked. Envy and jealousy sprang up, strife and dissension, aggression and rioting, scuffles and kidnappings. Men of the baser sort rose up against their betters: the rabble against the respectable, folly against wisdom, youth against its elders. And now all righteousness and peace among you is at an end. Everywhere men are renouncing the fear of God; the eye of faith has grown dim, and instead of following the commandments, and living as becomes a citizen of Christ, each one walks after the desires of his own wicked heart. All have fallen back into the horrid sin of Envy- the sin that brought death into the world.

19: Now it is not we alone who have been made better men by the self-effacement and humble submissiveness of all these famous personages, but generations of our predecessors as well, and indeed everyone who has ever received the utterances of God in fear and truth. Thus there exists a vast heritage of glorious achievements for us to share in. Let us then make haste and get back to the state of tranquility which was set before us in the beginning as the mark for us to aim at. Let us turn our eyes to the Father and Creator of the universe, and when we consider how precious and peerless are His gifts of peace, let us embrace them eagerly for ourselves. Let us contemplate Him with understanding, noting with the eyes of the spirit the patient forbearance that is everywhere willed by Him, and the total absence of any friction that marks the ordering of His whole creation.

20: The heavens, as they revolve beneath His government, do so in quiet submission to Him. The day and the night run the course He has laid down for them, and neither of them interferes with the other. Sun, moon, and the starry choirs roll on in harmony at His command, none swerving from its appointed orbit. Season by season the teeming earth, obedient to His will, causes a wealth of nourishment to spring forth for man and beast and every living thing upon its surface, making no demur and no attempt to alter even the least of His decrees. Laws of the same kind sustain the fathomless deeps of the abyss and the untold regions of the underworld. Nor does the illimitable basin of the sea, gathered by the operations of His hand into its various different centers, overflow at any time the barriers encircling it, but does as He has bidden it- for His word was, Thus far shall you come; at this point shall your waves be broken within you. The impassable ocean and all the worlds that lie beyond it are themselves ruled by the like ordinances of the Lord. Spring, summer, autumn, and winter succeed one another peaceably; the winds fulfil their punctual duties, each from its own quarter, and give no offense; the ever-flowing streams, created for our well-being and enjoyment, offer their breasts unfailingly for the life of man; and even the minutest of living creatures mingle together in peaceful accord. Upon all of these the great Architect and Lord of the universe has enjoined peace and harmony, for the good of all alike, but pre-eminently for the good of ourselves who have sought refuge in His mercies through our Lord Jesus Christ. To Him be glory and majesty for ever and ever, amen.

33: ...Even the Architect and Lord of the universe Himself takes a delight in working. In His supreme power He has established the heavens, and in His unsearchable wisdom set them in order. He divided the earth from the waters around it, and settled it securely on the firm foundation of His will, and at His word He called to life the beasts of the field that roam its surface. He formed the sea and its creatures, and confined them by His power. Above all, with His own sacred and immaculate hands he fashioned man, who in virtue of his intelligence is the chiefest and greatest of all His works and the very likeness of His own image....

37: So now, my friends, let us get on resolutely with our warfare under His unerring directions. Think of the men who serve our own commanders in the field, and the prompt and orderly obedience with which they go about their duties. Not all of them are marshals, generals, colonels, captains, or the like; nevertheless, each at his own level executes the orders of the emperor and the military chiefs. For the great cannot exist without the small, nor the small without the great. Every organism is composed of various different elements; and this ensures its own good. Take the body as an instance; the head is nothing without the feet, nor are the feet anything without the head. Even the smallest of our physical members are necessary and valuable to the whole body; yet all of them work together and observe a common subordination, so that the body itself is maintained intact.

Excerpts from the Epistles of Ignatius of Antioch:

Ignatius Theophorus was the bishop of the metropolitan See of Antioch in Syria. Of his origin, birth, and early life we know nothing at all with certainty. It has been surmised from hints in his letters that he was the son of pagan parents, and only converted to Christianity after reaching maturity. He appears to have become bishop of Antioch on the death in 69 A.D. of his predecessor Euodius. The date usually assigned to his martyrdom is 107, in the reign of the emperor Trajan. The provincial magistrates at Antioch sentenced him to be thrown to the wild beasts in the arena, and for this purpose dispatched him to Rome. At that time the provinces of the Empire were often required to supply criminals for the Roman circus.
The major themes of his epistles center on three principal ideas: the authority of the clergy, the hatred of heresy and schism, and the glory of martyrdom.

The Epistle to the Magnesians, 6: And now, since I have already seen with the eyes of faith and embraced your whole congregation, in the persons of the men I named, let me urge on you the need for godly unanimity in everything you do. Let the bishop preside in the place of God, and his clergy in place of the Apostolic enclave,1 and let my special friends the deacons be entrusted with the service of Jesus Christ, who was with the Father from all eternity and in these last days has been made manifest. Everyone should observe the closest conformity with God; you must show every consideration for one another, never letting your attitude to a neighbor be affected by your human feelings, but simply loving each other consistently in the spirit of Jesus Christ. Allow nothing whatever to exist among you that could give rise to any divisions; maintain absolute unity with your bishop and leaders, as an example to others and a lesson in the avoidance of corruption.

The Epistle to the Trallians, 3: Equally, it is for the rest of you to hold the deacons in as great respect as Jesus Christ; just as you should also look on the bishop as a type of the Father, and the clergy as the Apostolic circle forming His council; for without these three orders no church has any right to the name....

The Epistle to the Smyrnaeans , 8: Abjure all factions, for they are the beginning of evils. Follow your bishop, every one of you, as obediently as Jesus Christ followed the Father. Obey your clergy too, as you would the Apostles; give your deacons the same reverence that you would to a command from God. Make sure that no step affecting the church is ever taken by anyone without the bishop's sanction. The sole Eucharist you should consider valid is one that is celebrated by the bishop himself, or by some person authorized by him. Where the bishop is to be seen, there let all the people be; just as wherever Jesus Christ is present, we have the world-wide Church. Nor is it permissible to conduct baptisms or love-feasts without the bishop. On the other hand, whatever does have his sanction can be sure of God's approval too. This is the way to make certain of the soundness and validity of anything you do.

Excerpts from Libros Quinque Adversus Haereses (Five Books Against Heresies) by Irenaeus (Bishop of Lyons, c. 180).

On what grounds are heretics strangers and enemies to the apostles, if it is not from the difference of their teaching, which each individual of his own mere will has either advanced or received.

[the church] believes these points of doctrine just as if she had only one soul, and one and the same heart, and she proclaims them and teaches them in perfect harmony.... For although the languages of the world are different, still the meaning of the tradition is one and the same. For the churches which have been planted in Germany do not believe or hand down anything different, nor do those in Spain, nor those in Gaul, nor those in the east, nor those in Egypt, nor those in Africa, nor those which have been established in the central region of the world....

Suppose a dispute concerning some important question arises among us; should we not have recourse to the most ancient churches, with which the apostles held continual intercourse, and learn from them what is clear and certain in regard to the present question?

[Irenaeus prescribes terminating any disagreement] by indicating that tradition, derived from the apostles of the very great, the very ancient, and universally known church founded and organized at Rome by the two most glorious apostles, Peter and Paul... and by indicating the faith...which came down to our time by means of the succession of the bishops. For it is necessary that every church should agree with this church, on account of its preeminent authority.

Excerpt from the anonymous Epistle to Diognetus (c. middle of the 2nd century)
This text purports to be a reply to pagan's inquiry about the beliefs and customs of Christians.

The difference between Christians and the rest of mankind is not a matter of nationality, or language, or customs. Christians do not live apart in separate cities of their own, speak any special dialect, nor practice any eccentric way of life. The doctrine they profess is not the invention of busy human minds and brains, nor are they, like some, adherents of this or that school of human thought. They pass their lives in whatever township- Greek or foreign- each man's lot has determined; and conform to ordinary local usage in their clothing, diet, and other habits. Nevertheless, the organization of their community does exhibit some features that are remarkable, and even surprising. For instance, though they are residents at home in their own countries, their behaviour there is more like that of transients; they take their full part as citizens, but they also submit to anything and everything as if they were aliens. For them, any foreign country is a motherland, and any motherland is a foreign country.... Though destiny has placed them here in the flesh, they do not live after the flesh; their days are passed on the earth, but their citizenship is above in the heavens. They obey the prescribed law, but in their private lives they transcend the laws. They show love to all men- and all men persecute them. They are misunderstood, and condemned; yet by suffering death they are quickened into life. They are poor, yet making many rich; lacking all things, yet having all things in abundance. They are dishonoured, yet made glorious in their very dishonour; slandered, yet vindicated....
To put it briefly, the relation of Christians to the world is that of a soul to the body. As the soul is diffused through every part of the body, so are Christians through all the cities of the world. The soul, too, inhabits the body, while at the same time forming no part of it; and Christians inhabit the world, but they are not part of the world. The soul, invisible herself, is immured within a visible body; so Christians can be recognized in the world, but their Christianity itself remains hidden from the eye. The flesh hates the soul, and wars against her without any provocation, because she is an obstacle to its own self-indulgence; and the world similarly hates the Christians without provocation, because they are opposed to its pleasures. All the same, the soul loves the flesh and all its members, despite their hatred for her; and Christians, too, love those who hate them. The soul, shut inside the body, nevertheless holds the body together; and though they are confined within the world as in a dungeon, it is Christians who hold the world together. The soul, which is immortal, must dwell in a mortal tabernacle; and Christians, as they sojourn for a while in the midst of corruptibility here, look for incorruptibility in the heavens....

Excerpt from Tertullian's Apologeticus , XIX, 1:

Tertullian was born at Carthage c. 150-160 A.D., and was one of the greatest early Christian writers in Latin. He belonged to a pagan family and the circumstances of his conversion are unknown, but he became a Christian priest. He was especially learned in philosophy, science, and especially law. Of his early works the most interesting is his Apologeticus written in 197, in the form of the speech of an advocate addressed to the governors of Roman provinces, in which, with dignified eloquence, blending passion and irony, he seeks to secure for Christians protection from attacks of the populace. [Oxford Companion to Classical Literature]

Extreme antiquity gives books authority. For Moses was the first prophet. He began in the past with foundation of the world, the production of mankind, and later on the mighty cataclysm that avenged the iniquity of that age; by prophecy down to his own day and thereafter, in his own story he gave pictures of things yet to be. In his book the sequence of events set in order from the beginning has permitted the computation of the world's age. Moses then is discovered to have lived about three hundred years before your most ancient man Danaus had crossed to Argos; that means, he is about a thousand years earlier than the Trojan war, and consequently earlier than Saturn himself....
For Zacharias lived in the reign of Cyrus and Darius, at the very time when Thales, chief of the philosophers who wrote of Nature, could give no certain answer to Croesus's inquiry as to deity- perplexed, I suppose, by the words of the prophets. Solon told the same king that the end of a long life must be seen- much as the prophets did. So it can be seen that your laws and your studies alike were fertilized from the [Hebrew] law and teaching of God; the earlier must be the seed....
So all the subject matter, all the material, all the origins, chronologies, sources, of every ancient pen you know- yes, and most of your races, your cities, famous in history, hoary of memory- nay, the very shapes of your letters, those witnesses and guardians of the past- and (for I seem to be understanding things), I say, add your very gods, temples, oracles, rituals and all- the book of a single prophet notwithstanding beats them all, with centuries to spare,- that book in which is seen summed up the treasure of the whole Jewish religion, and in consequence of ours as well. If you chance, however, to have heard of one Moses, he is coeval with Argive Inachus, about four hundred years (to be exact less seven) before Danaus who is your most ancient man, a rough thousand years ahead of Priam's calamity. I might also say fifteen hundred years before Homer, with authority for saying so....

Selections from The Protreptikos (Exhortation to the Greeks) by Clement of Alexandria:

Clement is believed to have been born in Athens about 150. Educated in paganism and perhaps initiated into the mysteries, he traveled all over the world from school to school looking for a Doctrine and a Teacher. It was probably at Alexandria that he become a Christian, and there he settled down to teach until the persecution of Severus in 202 drove him away to Cappadocia. He is last heard of alive in 211, and is reported in 215 to be "among the blessed fathers."

Now it seems to me that since the Word Himself has come down from heaven to us, we no longer have any need for the schooling of men.
Nor need we get excited any more over Athens or the rest of Greece, or Ionia either.
For if we have as Master the One who fills all things with His sacred strength by the Creation, salvation and the doing of all good.
By His laws, prophecies, and teachings,
He is our teacher in all things,
And the whole world is now become Athens and Greece because of the Word.
Do not then give your belief to the poetic myth of Minos the Cretan living in fellowship with Zeus (Odyssey xix, 179), and refuse us your belief when we have become the disciples of God.
For we hold in trust the only true wisdom.
Which the greatest philosophers have barely glimpsed.
But which the disciples of Christ have received and announced to the world.
And indeed the whole Christ, if I may say so, is not divided.
He is not Barbarian or Jew or Greek, not man or woman.
He is the new man, made over entirely by the Holy Spirit of God (1 Corinthians i, 13).
Philosophy, the ancients tell us, is a prolonged consideration, aimed at attaining the eternal love of wisdom.
But the commandment of the Lord shines from afar, enlightening our eyes.
Receive Christ, receive sight, receive your light "in order to know well God and man" (Iliad 5:28).
"Delightful" is the Word that has enlightened us, "beyond gold and precious stones. More to be desired than honey and the honeycomb (Psalm xix, 10)."
How indeed should He not be desirable who has enlightened the mind that was buried in darkness,
Who has given sharp perception "to the light-bearing eyes of the soul?" (Plato, Timaeus, 45b) Just as "without the sun the other stars would leave the world plunged in night" (Herakleitos).
So too if we had not known the Word and had not ben illumined by His rays,
We would be no different from poultry stuffed with food in the dark,
For we would be in darkness, overfed and fattened for death.
Let us receive the Light, so that we may receive God.
Let us receive the Light and become disciples of the Lord.
For He has made this promise to the Father:
"I will make thy name known to my brothers: in the midst of the Church I will praise thee (Psalm xxii, 22)."
Sing to God thy Father and make Him known to me.
Thy words will save me, Thy song will teach me.
Up until now I have wandered far from the path in seeking God.
But since Thou dost enlighten me, O Lord, I find God through Thee,
I receive the Father from Thee,
I have become co-heir with Thee since Thou art not ashamed of Thy brother.
Let us put an end to our forgetfulness of truth.
Let us be rid of the ignorance, the darkness which veil our eyes like fog, and look upon the true God.
Acclaiming Him with the cry of "Hail, O Light."
Light from Heaven has shone upon us who were buried in the dark and prisoners in the shadow of death:
A light purer than the sun, and sweeter than the life this earth.
This ligtht is life everlasting, and everything that shares in it, lives.
But night avoids the light, hides in fear, and gives way to the Day of the Lord.
All has become unfailing Light, and the place of the setting sun has become the place of its rising.
Such is the meaning of the "new creature."
For the "sun of justice" passing over the whole world in its course, impartially visits all the family of man
In imitation of His Father "who makes His sun to rise upon all alike."
And He distills for them the dew of truth.
He it is who has changed the place of the sun's setting into a new east, death into life by His crucifixion.
Snatching man away from perdition He gives him a sure place in heave.
He takes up corruption and plants it in incorruption.
He transforms the earth into heaven.
He is God's farmer who sets up favorable signs and "calls the peoples forth to work" (Aratos) at good.
He reminds them of the way of life according to truth.
He endows us with a truly great, divine inheritance, coming from our Father,
An inheritance that cannot be lost.
He divinizes men by a heavenly teaching,
Giving laws to the their intellect and writing these laws in their heart.
What laws does He write in their hearts? These:
"All of the shall know God, from the little ones to the great ones."
"I shall be propitious to them," says God,
"And I shall no longer keep any memory of their sins."

XII: Let us shun custom; let us shun it as some dangerous headland, or threatening Charybdis , or the Sirens of legend. Custom strangles man; it turns him away from truth; it leads him away from life; it is a snare, an abyss, a pit, a devouring evil. "Wide of that smoke and wave direct, O helmsman, thy vessel (Odyssey, xii, 219-20)." Let us flee, comrades, let us flee from this wave. It belches forth fire; it is an island of wickedness heaped with bones and corpses (Odyssey, xii, 45-46), and she who things therein is pleasure, a harlot in the bloom of youth, delighting in her vulgar music. "Hither, renowned Odysseus, a great glory of all the Achaeans: Bring thy ship to the land, that a song divine may entrance thee (Odyssey, xii, 184-5)." She praises thee, sailor, she calls thee renowned in song; the harlot would make the glory of the Greeks her own. Leave her to roam among the corpses; a heavenly wind comes to thine aid. Pass by pleasure; she beguiles. "Let not thy heart be deceived by a woman with trailing garment, coaxing with wily words to find the place of thy dwelling (Hesiod, Works and Days, 373-4)." Sail past the song; it works death. Only resolve, and thou hast vanquished destruction; bound to the wood of the cross2 thou shalt live freed from all corruption. The Word of God shall by thy pilot and the Holy Spirit shall bring thee to anchor in the harbours of heaven. Then thou shalt have of the vision of my God, and shalt be initiated in those holy mysteries, and shalt taste the joys that are hidden away in heaven....

XII: ...Come, thou frenzy-stricken one, not resting on thy wand, not wreathe with ivy! Cast off thy headdress; cast of thy fawnskin; return to soberness! I will show thee the Word, and the Word's mysteries, describing them according to thine own semblance of them. This the mountain beloved of God, not a subject for tragedies, like Cithaeron, but one devoted to the dramas of truth, a wineless mountain, shaded by hallowed groves.... Come to me, old man, come thou too! Quit Thebes; fling away thy prophecy and Bacchic revelry and be led by the hand to truth. Behold, I give thee the wood of the cross to lean upon. Hasten, Teiresias,3 believe! Thou shalt have sight. Christ, by whom the eyes of the blind see again, shineth upon thee more brightly than the sun. Night shall flee from thee; first shall fear thee; death shall depart from thee. Thou shalt see heaven, old man, though thou canst not see Thebes.
O truly sacred mysteries! O pure light! In the blaze of the torches I have a vision of heaven and of God. I become holy by initiation. The Lord reveals the mysteries; He marks the worshipper with His seal, gives light to guide his way, and commends him, when he has believed, to the Father's care, where he is guarded for ages to come. These are the revels of my mysteries! If thou wilt, be thyself also initiated, and thou shalt dance with angels around the unbegotten and imperishable and only true God, the Word of God joining with us in our hymn of praise....

Pliny the Younger was appointed in 109 (or 110) by the Emperor Trajan as his personal legate in the Asian province of Bithynia-Pontus. Representing the authority of the Emperor, he served as a judge and arbiter in legal matters. A group of local citizens approached him to complain about Christians living in the vicinity. What precisely the complaint was we do not know, but from several hints in the letter it is possible to infer that the charge was brought by local merchants, perhaps butchers and others engaged in the slaughter and sale of sacrificial meat. Business was poor because people were not making sacrifices. In most areas of the Roman Empire, Christians lived quietly and peacably among their neighbors, conducting their affairs without disturbance. Only in those place where friction existed were local magistrates inclined to bring charges against Christians or to initiate legal action.

It is my custom to refer all my difficulties to you, Sir, for no one is better able to resolve my doubts and to inform my ignorance.
I have never been present at an examination of Christians. Consequently, I do not know the nature or the extendt of the punishments usually meted out to them, nor the grounds for starting an investigation and how far it should be pressed. Nor am I at all sure whether any distinction should be made between them on the grounds of age, or if young people and adults should be treated alike; whether a pardon ought to be granted to anyone retracting his beliefs, or if he has once professed Christianity, he shall gain nothing by renouncing it; and whether it is the mere name of Christian which is punishable, even if innocent of crime, or rather the crimes associated with the name.
For the moment this is the line I have taken with all persons brought before me on the charge of being Christians. I have asked them in person if they are Christians, and if they admit it, I repeat the question a second and third time, with a warning of punishment awaiting them. If they persist, I order them to be led away for execution; for, whatever the nature of their admission, I am convinced that their stubbornness and unshakable obstinacy ought not to go unpunished. There have been others similarly fanatical who are Roman citizens. I have them on the list of persons to be sent to Rome for trial.
Now that I have begun to deal with this problem, as so often happens, the charges are becoming more widespread and increasing in variety. An anonymous pamplet has been circulated which contains the names of a number of accused persons. Among these I considered that I should dismiss any who denied that they were or ever had been Christians when they had repeated after me a formula of invocation to the gods and had made offerings of wine and incense to your statue (which I had ordered to be brought into court for this purpose along with the images of the gods), and furthermore had reviled that name of Christ: none of which things, I understand, any genuine Christian can be induced to do.
Others, whose names were given to me by an informer, first admitted the charge and then denied it; they said that they had ceased to be Christians two or more years previously, and some of them even twenty years ago. They all did reverence to your statue and the images of the gods in the same way as the others, and reviled that name of Christ. They also declared that the sum total of their guilt or error amounted to nor more than this: they had met regularly before dawn on a fixed day to chant verses alternately among themselves in honour of Christ as if to a god, and also to bind themselves by a oath, not for any criminal purpose, but to abstain from theft, robbery, adultery, to commit no breach of trust and not to deny a deposit when called upon to restore it. After this ceremony it had been their custom to disperse and reassemble later to take food of an ordinary, harmless kind; but they had in fact given up this practice since my edict, issued on your instructions, which banned all political societies. This made me decide it was all the more necessary to extract the truth by torture from two slave-women, whom they call deaconesses. I found nothing but a degenerate sort of cult carried to extravagant lengths.
I have therefore postponed any further examination and hastened to consult you. The question seems to me to be worthy of your consideration, especially in view of the number of persons endangered; for a great many individuals of every age and class, both men and women, are being brought to trial, and this is likely to continue. It is not only the town, but villages and rural districts too which are infected through contact with this wretched cult. I think though it is still possible for it to be checked, and directed to better ends, for there is no doubt that people have begun to throng the temples which had been almost entirely deserted for a long time; the sacred rites which had been allowed to lapse are being performed again, and flesh of sacrificial victims is on sale everywhere, though up till recently scarcely anyone could be found to buy it. It is easy to infer from this that a great many people could be reformed if they were given an opportunity to repent.

You have followed the right course of procedure, my dear Pliny, in your examination of the cases of persons charged being Christians, for it is impossible to lay down a general rule to a fixed formula. These people must not be hunted out; if they are brought before you and the charge against them is proved, they must be punished, but in the case of anyone who denies that he is a Christian, and makes it clear that he is not by offering prayers to our gods, he is to be pardoned as a result of his repentance however suspect his past conduct may be. But pamphlets circulated anonymously must play no part in any accusation. They create the worts sort of precedent and are quite out of keeping with the spirit of our age.