Genesis 4:15-17

4:15 But the Lord said to him, “All right then, if anyone kills Cain, Cain will be avenged seven times as much.” Then the Lord put a special mark on Cain so that no one who found him would strike him down. 4:16 So Cain went out from the presence of the Lord and lived in the land of Nod, east of Eden.

The Beginning of Civilization

4:17 Cain had marital relations with his wife, and she became pregnant and gave birth to Enoch. Cain was building a city, and he named the city after his son Enoch.