The 5 Towns Jewish Times

This Week’s Daf Yomi Key Concepts: Parashas Nitzavim/Menachos

By Rabbi Shmuel Wise

Question: Does nullification apply to a mixture of similar items?

Answer: The daf of last Shabbos gave us the opportunity to review the Mishnah in Zevachim that discusses this question. The Mishnah there discusses a case where some sacrificial blood got mixed in with non-sacrificial blood. If there is a majority of non-sacrificial blood, do we say that the sacrificial blood is legally nullified and thus cannot be applied to the Mizbeiach? The rabbanan and R’ Yehuda debate this question: The rabbanan say the sacrificial blood is nullified and R’ Yehuda says it isn’t.

As the Gemara explains, the underlying question is what the rule is in a case of two similar items, as our case, where both elements in the mixture are blood. R’ Yehuda asserts that nullification does apply in this situation. Indeed, there is a powerful logic to what R’ Yehuda is saying: The whole idea of nullification is that the element of lesser quantity loses its identity to the element that makes up the majority of the mixture. How, then, does it make sense to say that blood loses its identity to blood? Thus R’ Yehuda says that the sacrificial blood doesn’t go away, no matter how much non-sacrificial blood is added to the mixture.

So what do the rabbanan say back? The Ran in Nedarim (52a) offers an interesting explanation. He says the rabbanan actually agree that if we were really dealing with two elements of the same type, nullification wouldn’t apply. However, the rabbanan argue that the two elements here are not considered the same: for one (the sacrificial blood) is permitted for the Mizbeiach and the other (the non-sacrificial blood) is prohibited for the Mizbeiach. In other words, the rabbanan hold that the “type” that a given item fits into depends not on its physical makeup but on its halachic makeup.

Things get even more interesting when we are presented on 23a with an Amoraic teaching about the exact understanding of R’ Yehuda’s opinion. The Gemara discusses what R’ Yehuda would rule for a mixture of kosher and non-kosher meat (i.e., from an animal that wasn’t properly slaughtered). Rav Chisda there states that if a bit of non-kosher meat mixed with a majority of kosher meat, the former would be halachically nullified (i.e., for the purposes of tumah; see Rashi there) — even according to R’ Yehuda. But wait—I thought R’ Yehuda says that nullification does not apply when the items of the mixture are of the same type?

As the Gemara there explains, Rav Chisda holds that since the majority item (i.e. the kosher meat) can never become like the minority item (the non-kosher meat — meaning that the kosher meat will never suddenly become a source of tumah like the non-kosher meat is), even R’ Yehuda agrees that this is judged as a mixture of dissimilar items and therefore nullification does apply. But this seems to only deepen the mystery. I thought R’ Yehuda goes by the physical makeup of the items when determining the type that an item is? Apparently, even R’ Yehuda agrees that we also have to put on our “halachic glasses” when judging what an item’s type is. That is, only when we see two items that are (a) physically the same and (b) can hypothetically become halachically the same will we judge this a mixture of items of the same type, which will not be subject to nullification.

Wishes to all for a sweet New Year filled with berachah and happiness!

Rabbi Wise is maggid shiur of Real Clear Daf, a website and mobile app that offers free audio shiurim and other resources to assist your journey through Shas. He is also the director of Tehillim Together, a mobile app (for iOS and Android) that offers a translated sefer Tehillim and facilitates Tehillim groups. To be a sponsor or to reach Rabbi Wise, please write to or call 855-ASK-RCD-1 (275-7231).