A Solemn Assembly is a sacred gathering in the Church which is held, most often, for the purpose of sustaining a new president and prophet of the church. Historically, solemn assemblies have also been held for dedication of temples or for specially called meetings to express the will of the church as a whole.
At the first general conference after the death of a church president and the calling of his successor, the session at which the sustaining vote takes place is called a Solemn Assembly. At a Solemn Assembly sustaining, groups of Latter-day Saints are asked to stand in succession and sustain the new president of the church. Typically, the order is: First Presidency, the Quorum of the Twelve, the Quorums of Seventy, the remaining Melchizedek Priesthood holders, Aaronic Priesthood holders, Relief Society members, members of the Young Women organization, and then all members together.The names of all other general authorities are then read, and a sustaining and opposing vote is called for.
The most recent solemn assembly sustaining of church officers of the church took place on April 5, 2008 at the church's Saturday morning session of general conference, where President Thomas S. Monson was sustained by the general membership as prophet, seer, and revelator of the church.
The Sunday morning session of the April 2000 general conference was also considered a Solemn Assembly in celebration of the Conference Center dedication.
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