Leviticus 25:4 (KJV)

And the LORD spake unto Moses in mount Sinai, saying,

Speak unto the children of Israel, and say unto them, When ye come into the land which I give you, then shall the land keep a sabbath unto the LORD.

Six years thou shalt sow thy field, and six years thou shalt prune thy vineyard, and gather in the fruit thereof;

That which groweth of its own accord of thy harvest thou shalt not reap, neither gather the grapes of thy vine undressed: for it is a year of rest unto the land.

And the sabbath of the land shall be meat for you; for thee, and for thy servant, and for thy maid, and for thy hired servant, and for thy stranger that sojourneth with thee.

And for thy cattle, and for the beast that are in thy land, shall all the increase thereof be meat.

And thou shalt number seven sabbaths of years unto thee, seven times seven years; and the space of the seven sabbaths of years shall be unto thee forty and nine years.

Then shalt thou cause the trumpet of the jubile to sound on the tenth day of the seventh month, in the day of atonement shall ye make the trumpet sound throughout all your land.