Leviticus 19:9-10

⁹And when ye reap the harvest of your land, thou shalt not wholly reap the corners of thy field, neither shalt thou gather the gleaning of thy harvest.

¹⁰And thou shalt not glean thy vineyard, neither shalt thou gather the fallen fruit of thy vineyard; thou shalt leave them for the poor and for the sojourner: I am Jehovah your God.