'Glean' in the Bible

" 'And at your reaping the harvest of your land you must not finish reaping the edge of your field, and you must not glean the remnants of your harvest.

And thou shalt not glean thy vineyard, neither shalt thou gather every grape of thy vineyard; thou shalt leave them for the poor and stranger: I am the LORD your God.

And when you reap the harvest of your land, you must not finish the edge of your field at your reaping, and you must not glean the remnants of your harvest--you shall leave them behind for the needy and for the alien; I [am] Yahweh your God.'"