Exodus 17:6

17:6 I will be standing before you there on the rock in Horeb, and you will strike the rock, and water will come out of it so that the people may drink.” And Moses did so in plain view of the elders of Israel.

Exodus 19:12

19:12 You must set boundaries for the people all around, saying, ‘Take heed to yourselves not to go up on the mountain nor touch its edge. Whoever touches the mountain will surely be put to death!