Our Lord Jesus Christ has instituted an office in His Church on earth. An office is a service, a ministry, vested with certain powers, a service performed in the name and at the command of some superior person. Such an office, which is to be administered in His name, our Lord and Saviour has instituted in His Church on earth. To what purpose? For the edifying of the body of Christ, that more and more people may be joined to Christ through faith, and be strengthened in such faith. What, therefore are the functions of this office? To preach the Gospel, to administer the Sacraments, and to forgive or to retain the sins to individual persons. To His disciples Jesus said: "All power is given to Me in heaven and in earth. Go, therefore, and teach all nations, baptising them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all things whatsoever I have commanded you. And, lo, I am with you always, even to the end of the world." (Matt. 28:18-20) And again He said to them: "Peace be unto you! As my Father has sent me, even so I send you." And when He said this, He breathed on them and said to them: "Receive the Holy Spirit: whosesoever sins you remit, they are remitted to them and whosesoever sins you retain, they are retained." (John 20:21-23) This office is called the "Office of the Keys", according to the saying of Christ: "I will give to you the keys of the kingdom of heaven." (Matt. 16:19) For by means of the Gospel, and the Sacraments connected with it, sins are forgiven. And where sins are forgiven, there heaven is opened. But if according to the Word of Christ sins are retained to any one, then heaven is closed to such a one.