Catena Aurea on Matthew 1:16: Augustine of Hippo

He is more properly called his son, by whom he was adopted, than had he been said to have been begotten of him of whose flesh he was not born. Wherefore Matthew, in saying, “Abraham begot Isaac,” and continuing the same phrase throughout down to “Jacob begot Joseph,” sufficiently declares that he gives the father according to the order of nature, so as that we must hold Joseph to have been begotten, not adopted, by Jacob. Though even if Luke had used the word, “begotten,” we need not have thought it any serious objection; for it is not absurd to say of an adopted son that he is begotten, not after the flesh, but by affection.