Leviticus 5:7-9

New Revised Standard Version, Anglicised Catholic Edition

⁷ But if you cannot afford a sheep, you shall bring to the Lord, as your penalty for the sin that you have committed, two turtle-doves or two pigeons, one for a sin-offering and the other for a burnt-offering. ⁸ You shall bring them to the priest, who shall offer first the one for the sin-offering, wringing its head at the nape without severing it. ⁹ He shall sprinkle some of the blood of the sin-offering on the side of the altar, while the rest of the blood shall be drained out at the base of the altar; it is a sin-offering.