Then He gave him the covenant of circumcision; and so Abraham begot Isaac and circumcised him on the eighth day; and Isaac begot Jacob, and Jacob begot the twelve patriarchs.
Acts 7:8
Surrounding context
7:7 "And the nation to whom they will be in bondage I will judge,' said God, "and after that they shall come out and serve Me in this place.'
7:8 Then He gave him the covenant of circumcision; and so Abraham begot Isaac and circumcised him on the eighth day; and Isaac begot Jacob, and Jacob begot the twelve patriarchs.
7:9 "And the patriarchs, becoming envious, sold Joseph into Egypt. But God was with him