Work with me here...
Upon this Rock, I will build my church. Rock = Christ. Rock = God throughout the entire bible. Don't take my word for it, do a search for yourself.
You claim the rock (petros, small stone) is what Christ builds his church on, but then a few verses later, Christ tells Peter that Satan is in him and he needs to repent.
So which is it...Rock = Christ which the church is built on. Or fallen man?