Acts 7:8

[8]And he gave him the covenant of circumcision: and so Abraham begat Isaac, and circumcised him the eighth day; and Isaac begat Jacob; and Jacob begat the twelve patriarchs. Ecclesiasticus 44:22

[22]With Isaac did he establish likewise for Abraham his father's sake the blessing of all men, and the covenant, And made it rest upon the head of Jacob. He acknowledged him in his blessing, and gave him an heritage, and divided his portions; among the twelve tribes did he part them.