Num 20:7-12
7 GOD spoke to Moses: 8 "Take the staff. Assemble the community, you and your brother Aaron. Speak to that rock that's right in front of them and it will give water. You will bring water out of the rock for them; congregation and cattle will both drink." 9 Moses took the staff away from GOD's presence, as commanded. 10 He and Aaron rounded up the whole congregation in front of the rock. Moses spoke: "Listen, rebels! Do we have to bring water out of this rock for you?"
11 With that Moses raised his arm and slammed his staff against the rock — once, twice. Water poured out. Congregation and cattle drank.
12 GOD said to Moses and Aaron, "Because you didn't trust me, didn't treat me with holy reverence in front of the People of Israel, you two aren't going to lead this company into the land that I am giving them."