Leviticus 5:8-10

8He shall bring them to the priest, who shall offer first the one for the sin offering. He shall awring its head from its neck bbut shall not sever it completely, 9and he shall sprinkle some of the blood of the sin offering on the side of the altar, while cthe rest of the blood shall be drained out dat the base of the altar; it is a sin offering. 10Then he shall offer the second for a burnt offering according to the rule. eAnd the priest shall make atonement for him for the sin that he has committed, and he shall be forgiven.

Leviticus 14:30-31

30And he shall offer, of the fturtledoves or pigeons, whichever he can afford, 31one
Septuagint, Syriac; Hebrew  afford, 31such as he can afford, one
for a sin offering and the other for a burnt offering, along with a grain offering. hAnd the priest shall make atonement before the Lord for him who is being cleansed.
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