If you just look at the Biblical text itself it becomes quite evident what Jesus was saying. He had just asked them, His disciples, who they thought He was. Peter spoke for all of them and stated, "You are the Messiah, the Son of the living God."
In Matt. 16:18 Jesus doesn’t say to Peter, “upon YOU I will build My church,” but “and upon THIS rock (petra) I will build My church.” “THIS” (Gr. toute) directly corresponds to the divinely revealed truth that Jesus is the promised Messiah, Second Person of the Trinity, God incarnate.
Jesus is divinely revealed to every person who personally believes in Him (see Jn. 14:21-22; 16:13-15) through the preaching of the Apostolic message of “the cross.” And it is these divinely enlightened who make up Christ’s Church which He Himself has been building since Pentecost, beginning with the Apostles (its foundation).
It’s all quite simple, folks. The true Church is all about Christ, not Peter. Redemption is all about Christ, not Peter, not the Church. The gifts of salvation, justification and eternal life are in Christ, not Peter, not the Church. Those who make up the Church Christ is building are the recipients of divine grace, not the source.
Funny how sola Scriptura can allow anyone to exegete Scripture in any way or fashion that they wish and come up with diametrically opposing views.

Here is a list of Protestant theologians who know koine Greek, know how to look at it objectively and who have concluded that Peter IS the Rock.
Gerhard Maier
leading conservative evangelical Lutheran theologian
Nowadays a broad consensus has emerged which — in accordance with the words of the text — applies the promise to Peter as a person. On this point liberal (H. J. Holtzmann, E. Schweiger) and conservative (Cullmann, Flew) theologians agree, as well as representatives of Roman Catholic exegesis.
“The Church in the Gospel of Matthew: Hermeneutical Analysis of the Current Debate”
Biblical Interpretation and Church Text and Context
(Flemington Markets, NSW: Paternoster Press, 1984), page 58
JPK pages 16-17
Donald A. Carson III
Baptist and Professor of New Testament at Trinity Evangelical Seminary
(two quotations from different works)
Although it is true that
petros and
petra can mean “stone” and “rock” respectively in earlier Greek, the distinction is largely confined to poetry. **Moreover the underlying Aramaic is in this case unquestionable; and most probably
kepha was used in both clauses (“you are
kepha” and “on this
kepha”), since the word was used both for a name and for a “rock”. **The Peshitta (written in Syriac, a language cognate with Aramaic) makes no distinction between the words in the two clauses. The Greek makes the distinction between
petros and
petra simply because it is trying to preserve the pun, and in Greek the feminine
petra could not very well serve as a masculine name.
The Expositor’s Bible Commentary:
Volume 8 (Matthew, Mark, Luke)
(Grand Rapids, MI: Zondervan, 1984), page 368
JPK pages 17-18
The word Peter
petros, meaning “rock” (Gk 4377), is masculine, and in Jesus’ follow-up statement he uses the feminine word
petra (Gk 4376). On the basis of this change, many have attempted to avoid identifying Peter as the rock on which Jesus builds his church.
Yet if it were not for Protestant reactions against extremes of Roman Catholic interpretations, it is doubtful whether many would have taken “rock” to be anything or anyone other than Peter.
Zondervan NIV Bible Commentary — New Testament, vol. 2
(Grand Rapids, MI: Zondervan, 1994), page 78
JPK page 18