Numbers 18:11-12

11And this is thine; the heave offering of their gift, with all the wave offerings of the children of Israel: I have given them unto thee, and to thy sons and to thy daughters with thee, by a statute for ever: every one that is clean in thy house shall eat of it.

12All the best of the oil, and all the best of the wine, and of the wheat, the firstfruits of them which they shall offer unto Yhwh, them have I given thee.1