Exodus 29:10

‘And he shall lay his hand on the head of the burnt offering, that it may be accepted for him to make atonement on his behalf.

Then he brought the bull of the sin offering, and Aaron and his sons laid their hands on the head of the bull of the sin offering.

“Now the Levites shall lay their hands on the heads of the bulls; then offer the one for a sin offering and the other for a burnt offering to Yahweh, to make atonement for the Levites.

‘When you have finished purifying it, you shall present a bull from the herd without blemish and a ram without blemish from the flock.

Slaughtering the Offerings