357. Put It in Cherim: The obligation to give proscribed property to a kohein
…any excluded item will be most holy to God. (Leviticus 27:28)
If someone declares one of his possessions to be cherim, that means that he forbids that object to himself. Such an object is to be given to a kohein unless he specified in his vow that it should go to the Temple instead.
The reason underlying this mitzvah is that the Jews have their possessions as a form of blessing from God. When a person imposes a vow of cherim on one of his objects, he typically does so in a fit of pique and it is intended as a curse. God does not permit him to change the object from a blessing to a curse but since the speaker clearly intends to have the object removed from his possession, God re-assigns its ownership to a kohein.
Items declared cherim go to the kohanim on duty at the time. (The kohanim were divided into 24 groups with a weekly duty rotation –see Mitzvah #509.) A field that a kohein receives in this manner does not revert to its original owner in the Jubilee. Property already belonging to kohanim and Leviim is immune to cherim. If a kohein or a Levi expresses a vow of cherim on an object of his, it has no effect since the property is already in the place where proscribed property ends up.
This mitzvah applies to both men and women in Temple times. Vows of cherim should not be made nowadays. If someone does so… well, let’s just say that things can get messy depending upon what one declared it upon –movable property, real estate, in Israel, out of Israel. Bottom line: don’t do it. If somebody did it, have them consult a rabbi.
This mitzvah is discussed in the Talmud in tractate Arachin on pages 28a-29a. It is codified in the Mishneh Torah in the sixth chapter of Hilchos Arachin and is #145 of the 248 positive mitzvos in the Rambam’s Sefer HaMitzvos.