Matthew 16:18 And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it.

What is this rock? Christ - the smitten rock in the wilderness out of which the water to live flowed: 1 Corinthians 10:4 ...for they drank of that spiritual Rock that followed them: and that Rock was Christ.

Thayer's Lexicon differentiates between "Peter" ("petros"): "a detached but large fragment" and "rock" ("petra"): "the massive living rock". Thus, Peter would be a chip off the rock.

Similarly, Jesus called Peter "Simon Barjona," which is "Simon son of Jona" (Matthew 16:17). Jesus compared Himself to Jonas: "For as Jonas was three days and three nights in the whale's belly; so shall the Son of man be three days and three nights in the heart of the earth." (Matthew 12:40) Peter became a son of Christ (Jona) by the gospel. All that obey the gospel become sons of God. (John 1:12-13).

Exodus 17:5-6 And the LORD said unto Moses...take...thy rod, wherewith thou smotest the river...Behold, I will stand before thee there upon the rock in Horeb; and thou shalt smite the rock, and there shall come water out of it, that the people may drink. (Horeb was where Israel received the Law. Jesus fulfilled the Law by His death.)

When the Lord told Moses to take his rod that he smote the river with, when the water poured out of the rock, God was bringing to remembrance blood, for when Moses smote the river with his rod, the water turned to blood.

This first time that Moses smote the rock represents Christ smitten on the cross. For out of Christ’s side came blood and water. (John 19:34).  This also represents water baptism in Jesus name. We are baptized into Christ’s death by baptism, and it is at baptism that His blood is applied to our life to wash away our sins. (Romans 6:3). The water at baptism has the remembrance of His blood that cleanses us of sin. (Acts 22:16).

The second time Moses struck the rock, Moses was to speak to the rock for the waters to come forth. This time the water would represent the Holy Ghost, for it is by belief and speaking that we receive the Holy Ghost. The Holy Ghost is compared to water: "He that believeth on me, as the scripture hath said, out of his belly shall flow rivers of living water. (But this spake he of the Spirit, which they that believe on him should receive: for the Holy Ghost was not yet given; because that Jesus was not yet glorified.)" - John 7:38-39 KJV

Numbers 20:8a Take the rod ... and speak ye unto the rock before their eyes; and it shall give forth his water...

Numbers 20:11 And Moses lifted up his hand, and with his rod he smote the rock twice: and the water came out abundantly...

Instead of believing the LORD that he and Aaron would bring forth water from the rock by their speaking, in anger Moses smote the rock twice, saying "ye rebels; must we fetch you water out of this rock?" (Numbers 20:10)

Numbers 20:12 ¶ 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.

Only those of faith, believing God, could enter into the land, which God had given them. Joshua and Caleb, the faithful witnesses that spied out the land, would enter, while Moses would not. It is by faith, not works, that we receive the promised gift of the Holy Ghost.

Thus, the rock is more than a revelation that Jesus is God incarnate: the rock represents the smiting of Christ and the subsequent pouring out of water represents His blood and Spirit.

It is upon the smitten rock – Christ – that the church is built. And it is by His blood and Spirit that the gates of hell cannot prevail! When the church baptizes souls in the name of Jesus and they are filled with His Spirit, the gates of hell cannot prevail against the church!