And he builded a city — In token of a settled separation from the church of God. And here is an account of his posterity, at least the heirs of his family, for seven generations. His son was Enoch, of the same name, but not of the same character with that holy man that walked with God. The names of more of his posterity are mentioned, and but just mentioned, as those of the holy seed, Genesis 5:1-32. They are numbered in haste, as not valued or delighted in, in comparison with God's children.
Related Commentaries of Genesis 4:17
Genesis 4:17
17 And Cain knew his wife; and she conceived, and bare Enoch:f and he builded a city, and called the name of the city, after the name of his son, Enoch.