Leviticus 5:6-8

New Revised Standard Version, Anglicised Catholic Edition

⁶ And you shall bring to the Lord, as your penalty for the sin that you have committed, a female from the flock, a sheep or a goat, as a sin-offering; and the priest shall make atonement on your behalf for your sin.

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.