19 And Lamech took two wives; the name of the one was Adah, and the name of the other Zillah. 20 Adah bore Jabal; he was the father of those who dwell in tents and have cattle. 21 His brother's name was Jubal; he was the father of all those who play the lyre and pipe. 22 Zillah bore Tubal-cain; he was the forger of all instruments of bronze and iron. The sister of Tubal-cain was Na'amah.

23 Lamech said to his wives: "Adah and Zillah, hear my voice; you wives of Lamech, hearken to what I say: I have slain a man for wounding me, a young man for striking me. 24 If Cain is avenged sevenfold, truly Lamech seventy-sevenfold."

25 And Adam knew his wife again, and she bore a son and called his name Seth, for she said, "God has appointed for me another child instead of Abel, for Cain slew him." 26 To Seth also a son was born, and he called his name Enosh. At that time men began to call upon the name of the Lord.

Matthew Henry's Commentary on Genesis 4:19-28

Commentary on Genesis 4:19-24

(Read Genesis 4:19-24)

One of Cain's wicked race is the first recorded, as having broken the law of marriage. Hitherto, one man had but one wife at a time; but Lamech took two. Wordly things, are the only things that carnal, wicked people set their hearts upon, and are most clever and industrious about. So it was with this race of Cain. Here was a father of shepherds, and a father of musicians, but not a father of the faithful. Here is one to teach about brass and iron, but none to teach the good knowledge of the Lord: here are devices how to be rich, and how to be mighty, and how to be merry; but nothing of God, of his fear and service. Present things fill the heads of most. Lamech had enemies, whom he had provoked. He draws a comparison betwixt himself and his ancestor Cain; and flatters himself that he is much less criminal. He seems to abuse the patience of God in sparing Cain, into an encouragement to expect that he may sin unpunished.

Commentary on Genesis 4:25-26

(Read Genesis 4:25-26)

Our first parents were comforted in their affliction by the birth of a son, whom they called Seth, that is, 'set,' 'settled,' or 'placed;' in his seed mankind should continue to the end of time, and from him the Messiah should descend. While Cain, the head of the apostacy, is made a wanderer, Seth, from whom the true church was to come, is one fixed. In Christ and his church is the only true settlement. Seth walked in the steps of his martyred brother Abel; he was a partaker of like precious faith in the righteousness of our God and Saviour Jesus Christ, and so became a fresh witness of the grace and influence of God the Holy Spirit. God gave Adam and Eve to see the revival of religion in their family. The worshippers of God began to do more in religion; some, by an open profession of true religion, protested against the wickedness of the world around. The worse others are, the better we should be, and the more zealous. Then began the distinction between professors and profane, which has been kept up ever since, and will be, while the world stands.