Numbers 20:12

Ye believed me not] The root of Moses' sin was unbelief. He doubted the power of God, or His willingness to bear longer with these rebels (Numbers 20:10), and instead of speaking to the rock, as he was commanded to do, he struck it twice: cp. Psalms 106:33. The punishment was severe, but want of faith on the part of the leaders could not be overlooked or unpunished, because the people had seen it, and might be led away by the evil example: see on Numbers 12:14. To sanctify me] God is always holy and His essential holiness cannot be increased. But the obedience and praise of His people cause His holiness and grace to be more widely known and acknowledged. Similarly God is said to be 'magnified,' as in Luke 1:46 : cp. the petition 'Hallowed be Thy name.'