From his Commentary on John (Book I):
19. (4) "In addition to these meanings there is that in which we speak of an arche, according to form; thus if the first-born of every creature (Colossians 1:15) is the image of the invisible God, then the Father is his arche. In the same way Christ is the arche of those who are made according to the image of God. For if men are according to the image, but the image according to the Father; in the first case the Father is the arche of Christ, and in the other Christ is the arche of men, and men are made, not according to that of which he is the image, but according to the image. With this example our passage will agree: 'In the arche was the Word.'"
22. "Not even as the Word is He the arche, for the Word was in the arche. And so one might venture to say that wisdom is anterior to all the thoughts that are expressed in the titles of the first-born of every creature. Now God is altogether one and simple; but our Saviour, for many reasons, since God (Romans 3:25) set Him forth a propitiation and a first fruits of the whole creation, is made many things, or perhaps all these things; the whole creation, so far as capable of redemption, stands in need of Him."