Exodus 17:5-7

5And the LORD said to Moses, Go on before the people, and take with thee of the elders of Israel; and thy rod, with which thou smotest the river, take in thy hand, and go. 6Behold, I will stand before thee there on the rock in Horeb; and thou shalt smite the rock, and water shall come out of it, that the people may drink. And Moses did so in the sight of the elders of Israel. 7And he called the name of the place Massah, and Meribah, because of the striving of the children of Israel, and because they tempted the LORD, saying, Is the LORD among us, or not?12