President Ezra Taft Benson (1899-1994) --
Between Moses and Christ only certain prophets possessed the right to the higher priesthood and the blessings that could bring men into the presence of God. One of these prophets was Elijah.
Elijah held the keys of the sealing power and did many mighty miracles in his day. He had power to seal the heavens, raise the dead, relieve the drought-stricken land, and call down fire from heaven.
He was the last prophet to hold the keys of the priesthood, according to the Prophet Joseph Smith. He was subsequently translated and taken up into heaven without tasting death.
He, as a translated being, restored the keys of this priesthood to the Savior’s chief Apostles—Peter, James, and John—on the Mount of Transfiguration. But within a generation, the Church was destroyed by a major apostasy, and the blessings of the priesthood were removed from the earth.
It took a new dispensation from heaven to restore this blessing to our day. ...
[The] Kirtland Temple was completed at great sacrifice to the Saints.
Then, on 3 April 1836, the Lord Jesus Christ and three other heavenly beings appeared in this holy edifice. One of these heavenly messengers was Elijah, to whom the Lord said he had “committed the keys of the power of turning the hearts of the fathers to the children, and the hearts of the children to the fathers, that the whole earth may not be smitten with a curse.” (Doctrine & Covenants 27:9.)
Elijah brought the keys of sealing powers—that power which seals a man to a woman and seals their posterity to them endlessly, that which seals their forefathers to them all the way back to Adam. This is the power and order that Elijah revealed—that same order of priesthood which God gave to Adam and to all the ancient patriarchs which followed after him.
And this is why the Lord said to the Prophet Joseph Smith, “For verily I say unto you, the keys of the dispensation, which ye have received, have come down from the fathers, and last of all, being sent down from heaven unto you.” (Doctrine & Covenants 112:32.)
( from President Ezra Taft Benson; "What I Hope You Will Teach Your Children about the Temple"; "Ensign"; August 1985.)The entire talk may be found at the following link: https://www.lds.org/ensign/1985/08/what-i-hope-you-will-teach-your-children-about-the-temple
