Joseph Smith had practical experience with the operation of the Holy Ghost. After he and Oliver Cowdery were baptized and ordained by priesthood authority, they received the Holy Ghost and were able to better understand the scriptures: “We were filled with the Holy Ghost, and rejoiced in the God of our salvation. Our minds being now enlightened, we began to have the scriptures laid open to our understandings, and the true meaning and intention of their more mysterious passages revealed unto us in a manner which we never could attain to previously, nor ever before had thought of” (Joseph Smith—History 1:73–74).

Joseph Smith was the greatest gospel restorer of all time, for the Lord had “given him the keys of the mystery of those things which have been sealed, even things which were from the foundation of the world” (DC 35:18). As leader of the dispensation of the fulness of times, it was in the very nature of his calling to be able to discuss in authoritative detail the conditions and function of all previous dispensations, including the time of the New Testament. He understood the New Testament better than anyone since Peter, James, John, and Paul.

Joseph Smith declared emphatically that the fulness of the gospel, with a focus on Christ as Creator and Redeemer, accompanied by priesthood, ordinances, covenants, and callings, was instituted in heaven before the foundation of the world. This complete gospel plan was preached in the name of Christ in every dispensation beginning with Adam. Sacred records and histories were kept by the authorized servants of God in each dispensation. The New Testament dispensation was unique in that it included the Lord’s birth, earthly life, death, and resurrection, but the doctrines and ordinances of salvation would of necessity be the same as in all other dispensations.