Genesis 24:2-4

So Abraham said to the oldest servant of his house, who ruled over all that he had, “Please, put your hand under my thigh, and I will make you swear by the LORD, the God of heaven and the God of the earth, that you will not take a wife for my son from the daughters of the Canaanites, among whom I dwell; but you shall go to my country and to my family, and take a wife for my son Isaac.”