You do the deeds of your father.
Then said they to him, We are not born of fornication; we have one Father, even God.
All Commentaries on John 8:41 Go To John 8
Augustine of Hippo
AD 430
The Jews had begun to understand that our Lord was not speaking of sonship according to the flesh, but of manner of life. Scripture often speaks of spiritual fornication, with many gods, and of the soul being prostituted, as it were, by paying worship to false gods. This explains what follows: Then said they to Him, We be not born of fornication; we have one Father, even God.
This then is the eternal procession, the proceeding forth of the Word from God: from Him. It proceeded as the Word of the Father, and came tous: The Word was made flesh. His advent is His humanity: His staying, His divinity. You call God your Father; acknowledge Me at least to be a brother.
And they could not hear, because they would not believe, and amend their lives.