Genesis 24:1-3

Young's Literal Translation

24 And Abraham [is] old, he hath entered into days, and Jehovah hath blessed Abraham in all [things];

² and Abraham saith unto his servant, the eldest of his house, who is ruling over all that he hath, `Put, I pray thee, thy hand under my thigh,

³ and I cause thee to swear by Jehovah, God of the heavens, and God of the earth, that thou dost not take a wife for my son from the daughters of the Canaanite, in the midst of whom I am dwelling;