The sons of Leah Jacob's first wife, which are six, and are reckoned in order, according to their birth, Reuben, Simeon, Levi, Judah, Issachar, Zebulun.
21
And Israel journeyed, and spread his tent on the other side of Migdal-Eder.
22
And it came to pass when Israel dwelt in that land, that Reuben went and lay with Bilhah, his father's concubine; and Israel heard of it. And the sons of Jacob were twelve.
23
The sons of Leah: Reuben -- Jacob's firstborn -- and Simeon, and Levi, and Judah, and Issachar, and Zebulun.