פירוש על קידושין 110:1

R. Yohanan is surprised by R. Oshaya’s explanation of the mishnah about the lost animal (see section one). Do we say to a person “Sin” by intentionally redeeming an animal intended to be offered as a sacrifice. An animal designated to be sacrificed cannot be redeemed unless it has become flawed and cannot be sacrificed. Even though he will have the merit of donating two sacrifices in its place, and thereby remedy the situation, we do not generally tell people to sin even if the sin will eventually result in merit.
Therefore, R. Yohanan has another suggestion. We wait until the animal is blemished. Then it is redeemed and we make a stipulation. If the animal was a burnt offering, then the first offering will be a burnt offering in its place and the second a voluntary peace offering. If the animal was a peace offering, the second animal is a peace offering in its place and the first offering is a voluntary burnt offering. After doing this, the animal he found is successfully desacralized. He may now eat it. Bon Appetit!