During the time he was living there, Reuben went and slept with Bilhah, his father's concubine, and Israel found out about it. These were the twelve sons of Jacob:
The descendants of Dan, men aged twenty or older, were recorded by name according to the genealogical records of their tribe and families. All those registered who could serve in the army
God also gave Abraham the agreement regarding circumcision, and so when Isaac was born, Abraham circumcised him on the eighth day. Isaac was the father of Jacob, and Jacob the father of the twelve patriarchs.