Exodus 17:3, 6

But the people were thirsty for water; and the people murmured against Moses and said, “Why did you bring us up from Egypt to kill us and our children and our livestock with thirst?”

Behold, I will stand before you there on the rock at Horeb; there you shall strike the rock, and water will come out of it, so that the people may [have something to] drink.” And Moses did so in the sight of the elders of Israel. [1 Cor 10:4]