John Gills Exposition of the Bible Commentary - Genesis 4:17
And Cain knew his wife ,.... Who this woman was is not certain, nor whether it was his first wife or not; whether his sister, or one that descended from Adam by another of his sons, since this was about the one hundred and thirtieth year of the creation. At first indeed Cain could marry no other than his sister; but whether he married Abel's twin sister, or his own twin sister, is disputed; the Jews say F7 Pirke Eliezer, c. 21. , that Cain's twin sister was not a beautiful woman, and... read more
Matthew Henry's Complete Commentary - Genesis 4:16-18
We have here a further account of Cain, and what became of him after he was rejected of God. I. He tamely submitted to that part of his sentence by which he was hidden from God's face; for (Gen. 4:16) he went out from the presence of the Lord, that is, he willingly renounced God and religion, and was content to forego its privileges, so that he might not be under its precepts. He forsook Adam's family and altar, and cast off all pretensions to the fear of God, and never came among good people,... read more