Genesis 22:10-13

Abraham stretched out his hand, and took the knife to kill his son. The LORD’s angel called to him out of the sky, and said, “Abraham, Abraham!” He said, “Here I am.” He said, “Don’t lay your hand on the boy or do anything to him. For now I know that you fear God, since you have not withheld your son, your only son, from me.” Abraham lifted up his eyes, and looked, and saw that behind him was a ram caught in the thicket by his horns. Abraham went and took the ram, and offered him up for a burnt offering instead of his son.