Behold, I will stand before you there upon the rock in Horeb; and you shall strike the rock, and there shall come water out of it, that the people may drink.
And Moses did so in the sight of the elders of Israel.
All Commentaries on Exodus 17:6 Go To Exodus 17
Ambrose of Milan
AD 397
The people of the fathers thirsted, Moses touched the rock, and water flowed out of the rock. Did not grace work a result contrary to nature, so that the rock poured forth water, which by nature it did not contain?.