"Behold I say unto you, that the law is fulfilled that was given unto Moses. Behold, I am he that gave the law, and I am he who covenanted with my people Israel: therefore, the law in me is fulfilled, for I have come to fulfil the law; therefore it hath an end. Behold, I do not destroy the prophets, for as many as have not been fulfilled in me, verily I say unto you, shall all be fulfilled." (Book of Mormon, 3 Nephi 15:4-6). A studious reading of the four Gospels demonstrates that while our Lord recognized the Jewish hierarchy as administrators of an existing system of government, and complied with all lawful requirements thereof as such applied to Himself, He proclaimed the Gospel of the Kingdom in place of the Mosaic Law, and ordained men to a higher Priesthood than that of Aaron under which the priests of the Jews claimed to operate. He commissioned the Twelve Apostles (Matt. 10:1; Mark 3:14; Luke 6:13), and afterward the Seventy (Luke 10:1). Unto the eleven Apostles who had remained faithful the Lord gave the parting instruction, shortly before His ascension: "Go ye into all the world, and preach the Gospel to every creature." The Apostles labored with devoted energy, "And they went forth, and preached every where, the Lord working with them, and confirming the word with signs following." (See Mark 16:15-20). The Apostles clearly understood that though the Master had passed from earth He had left with them authority and commandment to build up the Church as an established organization. One of their early official acts was to fill the vacancy in their own body, which had been created by the apostasy and death of Judas Iscariot. It is evident that they considered the apostolic body to comprise twelve members and that the needs of the Church required the organization to be made complete. By official action Matthias was added to the eleven. (See Acts 1:21-26). Under the administration of the Apostles and others who officiated by their direction in positions of lesser authority, the Church of Jesus Christ grew in membership and influence. For ten years or more following our Lord's ascension, Jerusalem was the headquarters of the Church, but branches were established in the outlying provinces, and these branches, or local "churches," were officered by bishops, deacons, and other ministers, who were chosen and ordained by apostolic authority. We find, operating in their sacred callings in the Primitive Church, apostles, prophets, evangelists, pastors, teachers, elders, bishops, priests and deacons. The purpose of these several offices is declared to be "For the perfecting of the saints, for the work of the ministry, for the edifying of the body of Christ." (Eph. 4:12).