Mishnayos Negaim Perek 14 Mishnah 11

הכל הולך אחר החטאת – for in the sin-offering and the burnt offering, the rich and poor are divided/separated, that the rich brings from the cattle, and the poor brings from the fowl, two turtle-doves or two pigeons, therefore, if at the time of the offering of the sin-offering, he was poor and he brought the sin offering of fowl, even though he became rich afterwards, he would supplement the sacrifice of the poor person and bring the burnt offering of a fowl. And similarly, if he was rich and he brought the sin-offering of cattle, even though he became poor, he needs to bring the burnt offering of cattle.

רבי יהודה אומר אחר האשם – that with regard to the guilt-offering, the poor and rich are equivalent, and it is the first of the sacrifices of the leper, and designated for his purification more than all others. And both of them are expounded upon from one Scriptural verse, as it is written (Leviticus 14:32): "אשר לא-תשיג ידו בטהרתו"/”and whose means for his purification are limited,” Rabbi Shimon holds that that which procures atonement for him, and that is the sin-offering. But Rabbi Yehuda holds the thing that makes him fit and purifies him, and that is the guilt-offering. And the Halakha is according to Rabbi Yehuda.