Exodus 23:9-11

9And the stranger thou shalt not oppress; for ye know the spirit of the stranger, for ye have been strangers in the land of Egypt.

10And six years thou shalt sow thy land, and gather in its produce;

11but in the seventh thou shalt let it rest and lie [fallow], that the poor of thy people may eat [of it]; and what they leave, the beasts of the field shall eat. In like manner thou shalt deal with thy vineyard, and with thine olive-tree.