Continual dropping wears away a stone.

If God can do anything he can make a stone so heavy that even he can't lift it. Then there is something God cannot do, he cannot lift the stone. Therefore God does not exist.

The water hollows out the stone, not by force but drop by drop.

To ask for power is forcing uphill a stone which after all rolls back again from the summit and seeks in headlong haste the levels of the plain.