Genesis 4:14-24

14 If thou castest me out this day from the face of the earth, and I shall be hidden from thy presence, and I shall be groaning and trembling upon the earth, then it will be that any one that finds me shall slay me.
15 And the Lord God said to him, Not so, any one that slays Cain shall suffer seven-fold vengeance; and the Lord God set a mark upon Cain that no one that found him might slay him.
16 So Cain went forth from the presence of God and dwelt in the land of Nod over against Edem.
17 And Cain knew his wife, and having conceived she bore Enoch; and he built a city; and he named the city after the name of his son, Enoch.
18 And to Enoch was born Gaidad; and Gaidad begot Maleleel; and Maleleel begot Mathusala; and Mathusala begot Lamech.
19 And Lamech took to himself two wives; the name of the one was Ada, and the name of the second Sella.
20 And Ada bore Jobel; he was the father of those that dwell in tents, feeding cattle.
21 And the name of his brother was Jubal; he it was who invented the psaltery and harp.
22 And Sella also bore Thobel; he was a smith, a manufacturer both of brass and iron; and the sister of Thobel was Noema.
23 And Lamech said to his wives, Ada and Sella, Hear my voice, ye wives of Lamech, consider my words, because I have slain a man to my sorrow and a youth to my grief.
24 Because vengeance has been exacted seven times on Cain's behalf, on Lamech's seventy times seven.

Footnotes 8

The Brenton translation of the Septuagint is in the public domain.