Genesis 24:2-5

2He said to the senior servant in his household, the one in charge of all that he had, “Put your hand under my thigh. 3I want you to swear by the Lord, the God of heaven and the God of earth, that you will not get a wife for my son from the daughters of the Canaanites, among whom I am living, 4but will go to my country and my own relatives and get a wife for my son Isaac.” 5The servant asked him, “What if the woman is unwilling to come back with me to this land? Shall I then take your son back to the country you came from?”