Leviticus 5:7-10
5:7 “‘If he cannot afford an animal from the flock, he must bring his penalty for guilt for his sin that he has committed, two turtledoves or two young pigeons, to the Lord, one for a sin offering and one for a burnt offering.
5:8 He must bring them to the priest and present first the one that is for a sin offering. The priest must pinch its head at the nape of its neck, but must not sever the head from the body.
5:9 Then he must sprinkle some of the blood of the sin offering on the wall of the altar, and the remainder of the blood must be squeezed out at the base of the altar – it is a sin offering.
5:10 The second bird he must make a burnt offering according to the standard regulation. So the priest will make atonement on behalf of this person for his sin which he has committed, and he will be forgiven.
Leviticus 14:19-20
14:19 “The priest must then perform the sin offering and make atonement for the one being cleansed from his impurity. After that he is to slaughter the burnt offering,
14:20 and the priest is to offer the burnt offering and the grain offering on the altar. So the priest is to make atonement for him and he will be clean.
Leviticus 14:30-31
14:30 “He will then make one of the turtledoves or young pigeons, which are within his means,
14:31 a sin offering and the other a burnt offering along with the grain offering. So the priest is to make atonement for the one being cleansed before the Lord.