D&C 18

We are familiar with the words of the Savior -

"...Blessed art thou, Simon Bar-jona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven.
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.
19 And I will give unto thee the keys of the kingdom of heaven: and whatsoever thou shalt bind on earth shall be bound in heaven: and whatsoever thou shalt loose on earth shall be loosed in heaven." (New Testament Matthew 16:17 - 19)

There have been many interpretations of "this rock". Some suggest it isrevelation while others claim that it is Peter himself. In modern revelation, the Lord said -

"...I give unto you a commandment, that you rely upon the things which are written;
4 For in them are all things written concerning the foundation of my church, my gospel, and my rock." (Doctrine and Covenants Section 18:3 - 4)

The Church, the gospel, and the rock seem to be interrelated but with seperate meanings. The Lord explains -

"Wherefore, if you shall build up my church, upon the foundation of my gospel and my rock, the gates of hell shall not prevail against you." (Doctrine and Covenants Section 18:5)

Again he talks of the foundation of my rock. And if so, the gates of hell will not prevail. As noted, the Lord follows this explanation of the rock with the statement that he will give Peter the keys of the kingdom of heaven.

Paul taught that -

"...he gave some, apostles; and some, prophets; and some, evangelists; and some, pastors and teachers;
12 For the perfecting of the saints, for the work of the ministry, for the edifying of the body of Christ." (New Testament Ephesians 4:11 - 12)

"...built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief corner stone..." (New Testament Ephesians 2:20)

I believe the rock then referred to is the priesthood and priesthood keys. It is upon this rock the Church could be built and the gospel so manifest. Having restored the priesthood and giving Oliver Cowdery and David Whitmer the charge to search out twelve apostles, the Lord suggests therefore -

"...you have my gospel before you, and my rock, and my salvation." (Doctrine and Covenants Section 18:17)

With priesthood keys restored, the foundation or rock was in place to build the Church, teach the gospel, and bring about His salvation.