St. John Chrysostom. Homily XII on St. Matthew
But why in the fashion of a dove? Gentle is that creature, and pure. Forasmuch then as the Spirit too is “a Spirit of meekness” (Galatians 6:1), He therefore appears in this sort.
And besides, He is reminding us of an ancient history. For so, when once a common shipwreck had overtaken the whole world, and our race was in danger of perishing, this creature appeared, and indicated the deliverance from the tempest, and bearing an olive branch, (Genesis 8) published the good tidings of the common calm of the whole world; all which was a type of the things to come.
For in fact the condition of men was then much worse, and they deserved a much sorer punishment. To prevent thy despairing, therefore, He reminds thee of that history. Because then also, when things were desperate, there was a sort of deliverance and reformation; but then by punishment, now, on the contrary, by grace and an unspeakable gift (2 Corinthians 9:15).
Therefore the dove also appears, not bearing an olive branch, but pointing out to us our Deliverer from all evils, and suggesting the gracious hopes. For not from out of an ark doth she lead one man only, but the whole world she leads up into heaven at her appearing, and instead of a branch of peace from an olive, she conveys the adoption to all the world’s offspring in common.