3,619. Challah

Hilchos Bikkurim 5:1

There is a Torah obligation to separate a portion of one’s dough and give it to a kohein, as per Numbers 15:20: “The first of your dough you shall raise as a gift.” Under Biblical law, there is no minimum size to this gift; even if someone put aside a portion the size of a barley grain, he would fulfill his obligation. If someone makes his entire dough challah, he has accomplished nothing unless he keeps a part of it for himself.

Hilchos Bikkurim 5:2

Under Rabbinic law, a person must separate 1/24 of his dough so that it will be a significant gift for the kohein. This is inferred from Deuteronomy 18:4: “Give him,” meaning something that qualifies as a suitable gift. A baker who makes dough to sell in the marketplace separates 1/48. Since his dough is larger, a smaller percentage is sufficient to make a suitable gift.