Then why did Jesus say otherwise?
1 Matthew 16:18 And I say to thee: That thou art Peter; and upon this rock I will build my church, and the gates of hell shall not prevail against it.
If you were not so determined to believe the religion of Rome we could lead you through the many Bible passages where JESUS teaches that believing on the One Whom God has sent for your salvation is the basis of the profession which THE HOLY SPIRIT led Peter to make, as Jesus told you in that scene.
But you are unable to learn from the Bible and you are now a captive of the magisterium, so showing you what Jesus says will not be received, you will only twist verses to ignore them or make untruths of them.
Can you in a sentence tell us what is The Gospel? What caused those thousands on the Day of Pentecost to be added THAT DAY tot he Church of Jesus The Christ?