Exodus 17:6
Behold, I will stand before thee there upon the rock in Horeb; and thou shalt smite 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.
Exodus 33:21
And the LORD said, Behold, there is a place by me, and thou shalt stand upon a rock:
Exodus 33:22
And it shall come to pass, while my glory passeth by, that I will put thee in a cleft of the rock, and will cover thee with my hand while I pass by: