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. (Leviticus 25:2)
The weekly Sabbath was made for man; now God announces a “sabbath” rest for the land also. All work on the land was to cease, and the land was to rest. What grew of itself might be used by anyone, rich or poor, including the stranger.