Matthew 16 has an interesting conversation between Jesus and his disciples.
Matthew 16:13-20 13When Jesus came into the coasts of Caesarea Philippi, he asked his disciples, saying, Whom do men say that I the Son of man am? 14And they said, Some say that thou art John the Baptist: some, Elias; and others, Jeremias, or one of the prophets.
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.
The disciples answered Jesus’s question about what other men were were saying about who Jesus was. When Jesus asked them specifically what they themselves thought, Peter jumped right in with a breath-taking statement that Jesus was the Messiah and the son of the living God. Sometimes we roll right over verses and miss some gold nuggets of truth. Jesus responds to Peter using his human name Simon Barjonas. It is clear that Peter did not understand this bedrock principle based on some human resource. Jesus is making it clear that God showed it to him. Wow! This is beautiful! (made me think of Romans 10:9-10). This whole concept is so important to all who believe. Jesus was the son of God! Standing right in front of Peter in the flesh was Christ, the second Adam (for Romans 5 fans)!
Jesus was excited that Peter knew and proceeds to tell him how important it is in the next couple of verses
And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell (the grave) 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. Then charged he his disciples that they should tell no man that he was Jesus the Christ.
Binding and loosing is a idiom for exercising authority. Later on in Matthew 18:18 others were given this authority. (Again Romans 10:9-10 comes to mind).
The context of this verse is in the resurrection. People referred to resurrections of Elijah, Jeremiah and John the Baptist in verse 14. Then Jesus referred to his own:
21 From that time forth began Jesus to shew unto his disciples, how that he must go unto Jerusalem, and suffer many things of the elders and chief priests and scribes, and bekilled, and be raised again the third day.