Kejadian 29:34

29:34 She became pregnant again and had another son. She said, “Now this time my husband will show me affection, ¹  because I have given birth to three sons for him.” That is why he was named Levi. ² 

Kejadian 35:22-26

35:22 While Israel was living in that land, Reuben had sexual relations with ³  Bilhah, his father’s concubine, and Israel heard about it.

Jacob had twelve sons:

35:23 The sons of Leah were Reuben, Jacob’s firstborn, as well as Simeon, Levi, Judah, Issachar, and Zebulun.

35:24 The sons of Rachel were Joseph and Benjamin.

35:25 The sons of Bilhah, Rachel’s servant, were Dan and Naphtali.

35:26 The sons of Zilpah, Leah’s servant, were Gad and Asher.

These were the sons of Jacob who were born to him in Paddan Aram.

[29:34]  ¹ tn Heb “will be joined to me.”

[29:34]  ² sn The name Levi (לֵוִי, levi), the precise meaning of which is debated, was appropriate because it sounds like the verb לָוָה (lavah, “to join”), used in the statement recorded earlier in the verse.

[35:22]  ³ tn Heb “and Reuben went and lay with.” The expression “lay with” is a euphemism for having sexual intercourse.

[35:22]  sn Reuben’s act of having sexual relations with Bilhah probably had other purposes than merely satisfying his sexual desire. By having sex with Bilhah, Reuben (Leah’s oldest son) would have prevented Bilhah from succeeding Rachel as the favorite wife, and by sleeping with his father’s concubine he would also be attempting to take over leadership of the clan – something Absalom foolishly attempted later on in Israel’s history (2 Sam 16:21-22).