Exodus 17:4-8

So Moses cried out to the Lord, saying, “What am I to do with this people? A little more and they will stone me!”

Then the Lord said to Moses, “Pass before the people and take with you some of the elders of Israel; and take in your hand your staff with which you struck the Nile, and go.

Behold, I will stand before you there on the rock at Horeb; and you shall strike the rock, and water will come out of it, so that the people may drink.” And Moses did so in the sight of the elders of Israel.

Then he named the place Massah and Meribah because of the quarrel of the sons of Israel, and because they tested the Lord, saying, “Is the Lord among us, or not?” Miraculous Battle against Amalek

Then Amalek came and fought against Israel at Rephidim.