"The earth was given to man, with this condition, that he should occupy himself in its cultivation... The custody of the garden was given in charge to Adam, to show that we possess the things which God has committed to our hands, on the condition that, being content with the frugal and moderate use of them, we should take care of what shall remain. Let him who possesses a field, so partake of its yearly fruits, that he may not suffer the ground to be injured by his negligence, but let him endeavor to hand it down to posterity as he received it, or even better cultivated. Let him so feed on its fruits, that he neither dissipates it by luxury, nor permits it to be marred or ruined by neglect. Moreover, that this economy, and this diligence, with respect to those good things which God has given us to enjoy, may flourish among us; let everyone regard himself as the steward of God in all things which he possesses. Then he will neither conduct himself dissolutely, nor corrupt by abuse those things which God requires to be preserved."

- John Calvin on Genesis 2.15 in Commentary on Genesis (1554).

The earth was given to us. And, at the same time, we were given to the earth, to till it and keep it.A recent study found that one quarter of the earth's arable land has been degraded through soil erosion, salinisation, desertification or nutrient exhaustion.