Book One: Genesis.
(Genesis 17:9) “And God said unto A’bra-ham, Thou shalt keep my covenant therefore, thou, and thy seed after thee in their generations. This is my covenant, which ye shall keep, between me and you and thy seed after thee; Every man child among you shall be circumcised. And ye shall circumcise the flesh of your foreskin; and it shall be a token of the covenant betwixt me and you. And he that is eight days old shall be circumcised among you, every man child in your generations, he that is born in the house, or bought with money of any stranger, which is not of thy seed. He that is born in thy house, and he that is bought with thy money, must needs be circumcised; and my covenant shall be in your flesh for an everlasting covenant. And the uncircumcised man child whose flesh of his foreskin is not circumcised, that soul shall be cut off from his people; he hath broken my covenant. “
(Genesis 24:2) “And A’-bra-ham said unto his eldest servant of his house, that ruled over all that he had, Put, I pray thee, thy hand under my thigh: And I will make thee swear by the LORD, the God of heaven, and the God of the earth, that thou shalt not take a wife unto my son of the daughters of the Ca’-na-an-ites, among whom I dwell: But thou shalt go unto my country and to my kindred, and take a wife unto my son I’-saac.”