Genesis 24:1-8

And Abraham was old, and well stricken in age: and Jehovah had blessed Abraham in all things. And Abraham said unto his servant, the elder 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 Jehovah, the God of heaven and the God of the earth, that thou wilt not take a wife for my son of the daughters of the Canaanites, among whom I dwell: but thou shalt go unto my country, and to my kindred, and take a wife for my son Isaac. And the servant said unto him, Peradventure the woman will not be willing to follow me unto this land: must I needs bring thy son again unto the land from whence thou camest? And Abraham said unto him, Beware thou that thou bring not my son thither again. Jehovah, the God of heaven, who took me from my father’s house, and from the land of my nativity, and who spake unto me, and who sware unto me, saying, Unto thy seed will I give this land; he will send his angel before thee, and thou shalt take a wife for my son from thence. And if the woman be not willing to follow thee, then thou shalt be clear from this my oath; only thou shalt not bring my son thither again.