I've heard many Christians say the command to let the land rest every seventh year is for agricultural purposes. God knows that in order for the land to be productive, you need to give it a year of rest. I'd like to suggest that idea is completely false. Guess what happens during the sixth year when the land has been tilled and worked for six long years... what does it do? In its greatest state of fatigue it produces twice as much! This is not an agricultural issue at all; it has nothing to do with agriculture except that God is dealing with an agriculturally dependent nation.