Pesachim 82 - Took the Passover meat out of Jerusalem!

The meat of the Passover lamb must stay within the walls of Jerusalem (the Old City). If one takes it out, it is disqualified. If this happens before the Passover Holiday itself, one must burn the disqualified meat right away. He cannot eat it, and any mitzvah should be done immediately - in this case, it is the mitzvah of burning disqualified offerings.

By contrast, if the owners of the sacrifice became ritually impure or died, we know that nobody will be able to eat the meat, but we cannot burn it. So, the meat is left overnight, and then it becomes the leftover sacrifice, and it can and must be burned. One cannot burn on on the first day of Passover because it is a Holiday, so he burns it on the following day.

Rabbi Yochanan ben Berokah compares the last case with the death of the sons of Aharon, where the sacrifice was burned immediately, and says that we should do the same.

Art: The Dying Man by Isidoro Grunhut