Dates: c. 397 Summary: Ambrose, commenting on Genesis 6:4 in his treatise on Noah, holds the angelic reading. He rejects the poets' notion that the giants were merely "children of the earth," asserting instead that they were begotten of angels and women, the name signifying their bodily magnitude. He then turns the passage to a moral lesson: the giants typify those who devote themselves to the flesh while neglecting the soul.
But there were giants in the earth in those days. The author of divine Scripture does not want those giants to be regarded as the children of the earth in the manner of poets, but asserts that they were generated from angels and women, whom he calls with this name, desiring to express their bodily magnitude.
— On Noah and the Ark, Chapter IV, historicalchristian.faith. Ambrose contrasts the scriptural account with pagan poetic myth, taking the "sons of God" as angels.
And let us consider, lest perhaps the giants are like humans who devote themselves to the worship of their flesh, but have no care for their souls… Therefore, they labour in vain, arrogantly claiming heaven through their proud desires, and devoting themselves to earthly works, who, by choosing the lower and despising the higher communion, are condemned by a more severe punishment, as if they willingly subject themselves to more serious sins.
— On Noah and the Ark, Chapter IV, historicalchristian.faith. Ambrose moralizes the giants as those who exalt the body and despise the soul.