Inscription on the Frame: Pictor Hubertus e Eyck . maior quo nemo repertus/ Incepit. pondus. q[ue] Johannes arte secundus/ [Frater perfunctus]. Judoci Vijd prece fretus. Versu sexta mai. vos collocat acta tueri.

The painter Hubert van Eyck, greater than whom no one was found, began [this work]; and Jan, his brother, second in art, having carried through the task at the expense of Jodocus Vyd, invites you by this verse on the sixth day of May, to look at what has been done.

(The year 1432 is given in the red chronogram of the last line (underscored above))