Leviticus 25:2-4

2“Speak to the Israelites and say to them: ‘When you enter the land I am going to give you, the land itself must observe a sabbath to the Lord. 3For six years sow your fields, and for six years prune your vineyards and gather their crops. 4But in the seventh year the land is to have a year of sabbath rest, a sabbath to the Lord. Do not sow your fields or prune your vineyards.