Leviticus 27:28 "Notwithstanding, a Cherem that a man shall vow to set aside for the L-rd..."

This Positive Mitzvah tells us that if a person declares an object or animal as Cherem, this means that he is vowing to set this object or animal aside for holy use.

That object must then be presented to the priest.

If the person says, "This object is Cherem to G‑d" then the object must be given for use in the Beit HaMikdash.