Temurah 4:3-4
Temurah 4:3
If a person put aside money to buy an animal for a sin offering and it got lost, so he put aside other money in its place but he didn’t buy the sin offering before the original money was found, he should combine the funds and take the money for the sin offering out of those pooled funds; the rest of the money is used to buy a freewill offering. Let’s say that someone put aside money to buy an animal for a sin offering and it got lost, he designated an animal as a sin offering in its place but he didn’t offer it before the money was found and the animal got blemished. In such a case, the animal is sold, he combines the proceeds with the found money, he buys a new sin offering from those pooled funds and the balance is used to buy a freewill offering. If he designated an animal for a sin offering and it got lost, so he put aside money in its place but he didn’t buy a new sin offering before the animal was found and it was blemished, then the animal is sold, he combines the proceeds with the found money, he buys a new sin offering from those pooled funds and the balance is used to buy a freewill offering. If he designated an animal for a sin offering and it got lost, so he designated another animal in its place but he didn’t offer it before the first animal was found and they are both blemished, then both animals are sold, he combines all the proceeds, buys a new sin offering from those pooled funds and a freewill offering from the balance. If he designated an animal for a sin offering and it got lost, so he designated another animal in its place but he didn’t offer it before the first animal was found and they are both unblemished, one of them is offered and the other is left to die; this is the opinion of Rebbi. The Sages say that no sin offering is left to die except for one that was found after its owners had already brought another. Similarly, no money must be tossed into the Dead Sea (i.e., destroyed) except for money that was found after the owners already brought a sacrifice.
Temurah 4:4
If a person designated an animal as a sin offering and it got blemished, he can sell it and use the proceeds to bring another animal. Rabbi Elazar ben Rabbi Shimon says that if the second animal was offered before the first animal was slaughtered, it must be left to die because the owner has already been granted atonement.