Numbers 15:17-21

And Jehovah spake unto Moses, saying, Speak unto the children of Israel, and say unto them, When ye come into the land whither I bring you, then it shall be, that, when ye eat of the bread of the land, ye shall offer up a heave-offering unto Jehovah. Of the first of your dough ye shall offer up a cake for a heave-offering: as the heave-offering of the threshing-floor, so shall ye heave it. Of the first of your dough ye shall give unto Jehovah a heave-offering throughout your generations.