He saith unto them, But whom say ye that I am? And Simon Peter answered and said, Thou art the Christ, the Son of the living God. And Jesus answered and said unto him, Blessed art thou, Simon Barjona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven. 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. 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. (Matthew 16:15-19 KJV)
Many Catholics use Matthew 16:19 as Peter is the cornerstone of the church. Even Jesus gave permission for Peter to start the church, it doesn’t means that he was the pope or cornerstone of all Christian churches. The word church means “a gathering of citizens called out from their homes into some public place, an assembly.” It is not about Peter or actual building.
Jesus wanted to establish the church that many people can come together to worship God and encourage each other. Some people may think that the Old Testament church is ceased. Even though we don’t do the animal sacrifice anymore, it does not mean the Old Testament church is useless. We still need present our sacrifice life to God. We still need to bring tithe for our storehouse. The ceremonial laws are fulfilled by Jesus Christ, but He summarized other laws with two simple commandments—love God and love people.
Church is not about building, but it’s about people who work for God to touch lives of other people into Christ.