3,617. The Gifts of Kohanim

Hilchos Bikkurim 4:14

First fruits, terumah, challah, misappropriated property repaid with an extra fifth, and the portions given from a slaughtered animal are the personal property of the kohein. He may use them to buy servants, real estate or non-kosher animals. A debtor can accept them as payment and a woman can accept them as payment for her kesubah. They may likewise be used to buy a sefer Torah.

Hilchos Bikkurim 4:15

First fruits and terumah may not be eaten by non-kohanim. As a rule, first fruits that got mixed with secular produce are permitted in the ratio of 101:1, the same as with terumah. However, if first fruits get mixed with the same species of secular produce in Jerusalem, the mixture is prohibited for even the smallest amount of first fruits, the same as with second tithe. This is because they’re in Jerusalem, the place where one eats them, so they’re like something that could be rectified. Even though first fruits are prohibited to non-kohanim in Jerusalem as well, even the smallest amount in a mixture renders it prohibited. Even if someone planted first fruits after they were brought to Jerusalem, the slightest amount of produce that grows from them will render a mixture prohibited. However, if someone plants first fruits before they were brought to Jerusalem, what grows from them is secular produce.