Leviticus 5:7-8

7“But if you cannot afford to bring a sheep, you may bring to the Lord two turtledoves or two young pigeons as the penalty for your sin. One of the birds will be for a sin offering, and the other for a burnt offering.

8You must bring them to the priest, who will present the first bird as the sin offering. He will wring its neck but without severing its head from the body.