Paul addresses the Thessalonians and explains that he came unto them in word and power;
“For our gospel, came not unto you in word only, but also in power, and in the Holy Ghost, and in much assurance; as ye know what manner of men we were among you for your sake.” (1 Thessalonians 1:5)
This chapter, although short, is very powerful. Paul explains that he is not just a minister of word, but actually has POWER from God. This power or “Authority” is necessary in the ordinances of the gospel and is needed for the TRUE Church of Jesus Christ.
In the Church of Jesus Christ of Latter-day Saints, the power of the Priesthood and its restoration began on May 15, 1829 when the resurrected John the Baptist appeared to Joseph Smith and Oliver Cowdery to confer the Aaronic Priesthood upon them.