Leviticus 23:21-22

21And ye shall make proclamation on that same day — a holy convocation shall it be unto you: no manner of servile work shall ye do: [it is] an everlasting statute in all your dwellings throughout your generations.

22And when ye reap the harvest of your land, thou shalt not in thy harvest entirely reap the corners of thy field, and the gleaning of thy harvest shalt thou not gather: thou shalt leave them unto the poor and to the stranger: I am Jehovah your 1God.