If someone declared, "It is hereby incumbent upon me to bring a burnt offering," he then designated a specific ox as the offering. Another person came and stole it; the one who promised the offering is required to replace it. However, the thief can exempt himself from further liability with a lamb, which satisfies the obligation.
Suppose the thief sold all of the stolen animal, except one-hundredth of it, or slaughtered it and made a mistake in the slaughtering so that it became non-kosher in his hands. In that case, he pays the twofold payment of an ordinary thief but doesn't pay the fourfold or fivefold payment.
Art: A Thief by Fernando Botero