Because ye believed me not, to sanctify me

"Take the rod, and gather thou the assembly together, thou, and Aaron thy brother, and speak ye unto the rock before their eyes; and it shall give forth his water, and thou shalt bring forth to them water out of the rock: so thou shalt give the congregation and their beasts drink." - Numbers 20:8 KJV

God told Moses and Aaron that the water would come forth when they spoke to the rock.

"And Moses and Aaron gathered the congregation together before the rock, and he said unto them, Hear now, ye rebels; must we fetch you water out of this rock? And Moses lifted up his hand, and with his rod he smote the rock twice: and the water came out abundantly, and the congregation drank, and their beasts also." - Numbers 20:10-11 KJV

The LORD told Moses and Aaron that their action of striking the rock showed they did not believe Him. The LORD had said, if you speak to the rock, you will bring the water out of the rock. By striking the rock in their unbelief, they did not sanctify Him. To sanctify means, “to honour, to treat as sacred.”

"And the LORD spake unto Moses and Aaron, Because ye believed me not, to sanctify me in the eyes of the children of Israel, therefore ye shall not bring this congregation into the land which I have given them." - Numbers 20:12 KJV

The Bible says that that rock that Moses struck was Christ. (1 Corinthians 10:1-4). Moses striking the rock was a type and shadow of Christ being smitten. Christ suffered and died at the hands of His people because they didn’t believe that Jesus is God. They did not sanctify their Savior.

"He came unto his own, and his own received him not." - John 1:11 KJV

"I and my Father are one. Then the Jews took up stones again to stone him. Jesus answered them, Many good works have I shewed you from my Father; for which of those works do ye stone me? The Jews answered him, saying, For a good work we stone thee not; but for blasphemy; and because that thou, being a man, makest thyself God." - John 10:30-33 KJV

"If I do not the works of my Father, believe me not. But if I do, though ye believe not me, believe the works: that ye may know, and believe, that the Father is in me, and I in him. Therefore they sought again to take him: but he escaped out of their hand," - John 10:37-39 KJV

"Jesus said unto them, Verily, verily, I say unto you, Before Abraham was, I am. Then took they up stones to cast at him: but Jesus hid himself, and went out of the temple, going through the midst of them, and so passed by." - John 8:58-59 KJV

"But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name: which were born, not of blood, nor of the will of the flesh, nor of the will of man, but of God." - John 1:12-13 KJV (Acts 2:38-39).