Genesis 4:25
Douay-Rheims
Adam also knew his wife again: and she brought forth a son, and called his name Seth, saying: God hath given me another seed, for Abel whom Cain slew.
Augustine of Hippo
It is quite possible that when Adam was divinely inspired to say, after Seth was born, "God has given me another seed, for Abel whom Cain slew," there is no implication here that Seth was the next born in the order of time but only that he was destined to be a fit heir in the order of holiness.
Source details
A.D. 430 · on Gen 4:25 (City of God 15.15)
Imported from an open dataset — not yet checked against the printed edition.