Lev 25:3-5

3Six years you shall sow your field, and six years you shall prune your vineyard, and gather in their yield;4but in the seventh year there shall be a sabbath of complete rest for the land, a sabbath for the Lord: you shall not sow your field or prune your vineyard.5You shall not reap the aftergrowth of your harvest or gather the grapes of your unpruned vine: it shall be a year of complete rest for the land.