As the church's senior apostle, President Hinckley is the man designated to issue a calling that church members believe is inspired by God to men who will fill the vacancies in the quorum. "Apostles are chosen through inspiration," according to the Encyclopedia of Mormonism. The men so designated are then sustained by the "common consent" of Latter-day Saints who raise their right hands in affirmation during a general conference of the church, the next of which is scheduled the first weekend in October.
Designated to serve as "special witnesses" of Jesus Christ throughout the world, new designees are ordained to the office of apostle in the Melchizedek Priesthood. The ordination involves members of the First Presidency and Quorum of the Twelve, who lay their hands on the new apostle's head and bestow specific "keys of the priesthood" that include "all the keys, all the gifts, all the endowments and everything preparatory to entering into the presence of the Father and of the Son," according to Brigham Young, who served as second president of the church.
Apostles serve the church full time and hold the office for the duration of their lives, traveling throughout the world to oversee the faith's affairs.
The procedure for naming new apostles differs from that of naming a new church president and is not contingent upon the individual holding any specific office within the church. A new apostle may be chosen from among other general authorities of the church, or from among active and worthy Latter-day Saint men who hold the faith's "higher" or Melchizedek Priesthood.
Succession in the presidency of the church comes into play upon the death of the church's president. When that occurs, the senior apostle the man who holds the senior rank among the First Presidency and Quorum of the Twelve then becomes the next president of the church.
The procedure for succession was established after the death of church founder and the faith's first president, Joseph Smith, in 1844, after a dispute arose as to who would then lead the church. It has been followed ever since, though the Encyclopedia of Mormonism states that, "since a fundamental doctrine of the church is the reality of continuing revelation, and since the Twelve Apostles are sustained as prophets, seers and revelators, there is no apparent reason that the Quorum of the Twelve could not depart from this precedent and select someone other than the senior apostle to lead the church, if so directed by revelation."
If it were to occur, such a revelation "must come through the senior apostle" upon the president's death and must "be approved by unanimous vote of the members of the quorum."
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