Genesis 22:2

22:2 God said, “Take your son – your only son, whom you love, Isaac – and go to the land of Moriah! Offer him up there as a burnt offering on one of the mountains which I will indicate to you.”

Genesis 22:16

22:16 and said, “‘I solemnly swear by my own name,’ decrees the Lord, ‘that because you have done this and have not withheld your son, your only son,