I made a mistake. Now what should I do? TB Pesakhim 72

Today’s daf TB Pesakhim 72 clarifies the disagreement when somebody unwittingly violated the Shabbat because he thought he was doing a mitzvah (טועה בדבר מצוה-to’eh bedavar mitzvah) between Rabbi Eliezer, Rabbi Yehoshua, and Rabbi Meir. Everybody agrees that the forbidden action always remains forbidden. They disagree whether the person is obligated to bring a sin offering (חטאת) or not. Almost all of today’s cases happens with the intersection between some kind of mistake concerning a sacrifice and Shabbat. An example would be offering the Paschal Lamb for some other kind of sacrifice on Shabbat. Now this Paschal Lamb becomes ineligible to fulfill a person’s obligation of the korban Pesakh. By being ineligible, the person sacrificing this animal has violated the Shabbat by offering an uncalled for sacrifice.

Rabbi Eliezer doesn’t subscribe at all to the principal of to’eh bedavar mitzvah at all; consequently, the one who violated Shabbat must always bring a sin offering. Rabbi Yehoshua subscribes to the principal of to’eh bedavar mitzvah with some caveats. Even though the action is forbidden, he is exempt from bringing the sin offering. The caveats are: 1, the person must attempt to do a mitzvah; 2, the person must fulfill a mitzvah; 3, there must be a plausible explanation why you’re doing it. 

Here is the Gemara’s example of a implausible explanation as opposed to an plausible explanation. “The mishna continues with what Rabbi Eliezer said to Rabbi Yehoshua: Let the communal offerings prove the matter, for they are permitted for slaughter on Shabbat for their own purpose, and nevertheless, one who unnecessarily slaughters different offerings for their purpose is liable. Rabbi Yehoshua said to him: No, if you said this halakha with regard to communal offerings, it is because they have a limit. But can you necessarily say the same thing with regard to the Paschal lamb, which does not have a limit? ” (Sefaria.org translation) The committal offerings are the two temidim, one sacrificed in the morning and the other in the afternoon. Rabbi Yehoshua holds that the person offering up another tamid after the official one has already been sacrificed is liable for a sin offering. Keeping track of two sacrifices is pretty easy as opposed to the seemingly countless number of Passover sacrifices; consequently, the underlying reason for the mistake is not a plausible explanation.

Rabbi Meir has the most expensive application of to’eh bedavar mitzvah. The person is always exempt from bringing a sin offering when he’s made a mistake because he thought he is doing a mitzvah with only two caveats. Caveat #1, When the person is preoccupied doing the mitzvah, like sacrificing an animal and mistakenly offers up the wrong kind of animal, he is exempt from bringing a sin offering. Once an animal is consecrated for one type of sacrifice it cannot be repurposed for another. Caveat #2, The animal can easily be confused with the one set aside as an offering. 

In most cases brought down in the Gemara, one does not get a free pass when somebody unwittingly violated the Shabbat because he thought he was doing a mitzvah (טועה בדבר מצוה-to’eh bedavar mitzvah). Before you do something that is the exception to the rule of Shabbat violations, I suggest to double check everything to make sure you don’t accidentally make a mistake. To mix metaphors, remember the old carpenter’s advice of measure twice and cut once.