Exodus 17:3, 6

But the people thirsted there for water; and they grumbled against Moses and said, “Why, now, have you brought 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; and you shall strike the rock, and water will come out of it, that the people may drink.” And Moses did so in the sight of the elders of Israel.