Why was a Restoration of the Gospel needed? Haven’t we always had the Bible?
When Jesus Christ lived on the earth, He established His Church. After His Ascension into heaven, His Apostles carried on His work under His direction, through revelation and with His priesthood authority.
After the Apostles and many righteous Church members were killed and other members departed from the truth, the Lord took the priesthood authority and His Church from the earth. Without God’s priesthood authority, the Church no longer functioned as Christ had established it. The ordinances were changed and many plain and simple truths were lost. While many good people and some truth remained, the original Church was lost.
The Apostles prophesied of the falling away or Apostasy. One example is Paul’s letter to the Thessalonians (2 Thessalonians 2:1-3).
The Apostle Peter prophesied of the “restitution of all things” before Christ’s Second Coming (Acts 3:19-21). Having been lost because of the Apostasy, Christ’s Church and His authority were to be restored to the earth. This Restoration would make available the opportunity for all to receive once again all of the blessings of the gospel of Jesus Christ.
Joseph Smith’s First Vision marked the beginning of the Restoration of the gospel of Jesus Christ to the earth. In subsequent years, Christ restored His priesthood and reorganized His Church. He has continued to reveal truths to His prophets and to restore the blessings that were taken from the earth for a time.