2,455. Two Prohibitions That Combine

Maachalos Assuros 16:12

Pursuant to the previous halacha, it is prohibited to open the nuts, pomegranates, barrels, etc. after they have been rendered prohibited in an attempt to nullify the prohibition in 201 times its volume because we don’t intentionally nullify prohibitions. If one does so, he is penalized him by having the result prohibited to him, as has already been discussed.

Maachalos Assuros 16:13

Let’s say that yeast from mixed species of a vineyard and yeast from trumah fall into a dough; there’s not enough of either to make the dough rise but there’s enough in both together to make it rise. In such a case, the dough is prohibited to Yisroelim (“Israelites”) but it’s permitted to kohanim. Similarly, if spices of trumah and spices of mixed species of a vineyard fall into a pot and there’s not enough of either to season the dish, but there’s enough of both together to season it, that food is prohibited to Yisroelim. This is because it’s seasoned with something prohibited to them but permitted to kohanim.