Leviticus 8:23-24

Moses slaughtered the ram and took some of its blood and put it on Aaron’s right earlobe, on the thumb of his right hand, and on the big toe of his right foot.

Moses also presented Aaron’s sons and put some of the blood on their right earlobes, on the thumbs of their right hands, and on the big toes of their right feet. Then he sprinkled the blood on all sides of the altar.