Genesis 22:12-13

And he said, Lay not thy hand upon the lad, neither do thou anything unto him; for now I know that thou fearest God, seeing thou hast not withheld thy son, thine only son, from me. And Abraham lifted up his eyes, and looked, and, behold, behind him a ram caught in the thicket by his horns: and Abraham went and took the ram, and offered him up for a burnt-offering in the stead of his son.