The Rock is and was Christ Jesus.
Jesus never had any intention that the foundation of His church would be built on a man. All men and women are sinner, and continue to be sinners, but by repentance and accept of Christ Jesus, we become sinners saved by Grace, and start a New life in Him, byt eh help of The Holy Spirit.
Matthew 16 verse 18: Amplified Bible:
“And I tell you, you are Peter [Petros, masculine, a large piece of rock], and on this rock [Petra, feminine, a huge rock like Gibraltar] I will build My church, and the gates of Hades [the powers of the infernal region] shall not overpower it— or be strong to it’s detriment, or hold out against it.”
Jesus was saying to Peter, that Peter’s Statement of Faith, “You are The Christ, The Son of the Living God, was the Rock, and that He would build a church upon this great statement of Faith that acknowledge The Deity of Christ.
The Rock was and is Christ Jesus, ‘Come, let us shout joyfully to the Lord, shout triumphantly to the Rock of our Salvation.” Psalm 95 verse 1:
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