“Better do a study on what the “keys” meant to Old Testament Jews. It was the “keys” to the information of the Kingdom. Not who was let in or out but who was given the information about the Kingdom and how to conduct themselves. Jesus was giving the “keys” or the information about salvation and how Christians should conduct themselves.”
Isaiah 22:10, shows just the opposite. I’m glad to see that you’re familiar with the argument. Because you wouldn’t be making this one without me not already having made this argument further up.
The Keys are the symbol of God’s authority - Christ is giving St. Peter the authority to forgive sins. He is acting as Christ’s representative here in earth, and most of all, the office is to be passed onto Peter’s successors. Just like the Keys to the Davidic kingdom.
What the 12 bound on earth was bound in heaven and what was loosed on earth was loosed in heaven. They were to preach the gospel to every creature. But lookie here, in Galatians. "When James, Cephas (Peter), and John, who seemed to be pillars, PERCEIVED THE GRACE that was given unto me, they gave to me and Barnabas the right hand of fellowship; that WE SHOULD GO TO THE HEATHEN, and THEY UNTO THE CIRCUMCISION."
They loosed themselves from their commission to take the gospel to every nation, and gave Paul the right hand of fellowhsip to take HIS GOSPEL OF THE GRACE OF GOD TO THE GENTILES. Peter and the 11 confined their ministry to the Jews.
Now if you believe you are a Jew, then maybe you would have an argument regarding Peter's "successors". But Israel has been blinded and set aside until the fulness of the Gentiles be brought in. So it does you absolutely no good to claim to be Israel today. The Body of Christ is made up of neither Jew nor Gentile, male nor female, etc. So, the question is, WHAT "successors" to Peter? What exactly would they "succeed" him WITH? The only question remaining should be "why did Peter and the 11 loose themselves from the commission given to them by Christ? And make no mistake, it was not an accident. It was not laziness, or an inability to fulfill their commission. It was COMPLETELY IN LINE with God's Plan. And they perceived that when Paul and Barnabas told them "that gospel they preach unto the heathen".
No, He wasn’t.
Matthew 16:19 I will give you the keys of the kingdom of heaven; whatever you bind on earth will be bound in heaven, and whatever you loose on earth will be loosed in heaven."
Barne’s notes on the Bible
And I will give unto thee ... - A key is an instrument for opening a door.
He that is in possession of it has the power of access, and has a general care of a house. Hence, in the Bible, a key is used as a symbol of superintendence an emblem of power and authority. See the Isaiah 22:22 note; Revelation 1:18; Revelation 3:7 notes. The kingdom of heaven here means, doubtless, the church on earth. See the notes at Matthew 3:2. When the Saviour says, therefore, he will give to Peter the keys of the kingdom of heaven, he means that he will make him the instrument of opening the door of faith to the world the first to preach the gospel to both Jews and Gentiles. This was done, Acts 2:14-36; 10. The "power of the keys" was given, on this occasion, to Peter alone, solely for this reason; the power of "binding and loosing" on earth was given to the other apostles with him. See Matthew 18:18. The only pre-eminence, then, that Peter had was the honor of first opening the doors of the gospel to the world.
Whatsoever thou shalt bind ... - The phrase "to bind" and "to loose" was often used by the Jews. It meant to prohibit and to permit. To bind a thing was to forbid it; to loose it, to allow it to be done. Thus, they said about gathering wood on the Sabbath day, "The school of Shammei binds it" - i. e., forbids it; "the school of Hillel looses it" - i. e., allows it. When Jesus gave this power to the apostles, he meant that whatsoever they forbade in the church should have divine authority; whatever they permitted, or commanded, should also have divine authority - that is, should be bound or loosed in heaven, or meet the approbation of God. [http://bible.cc/matthew/16-19.htm]