In the Church of Jesus Christ of Latter-day Saints —Mormonism's largest denomination—there have been numerous changes to temple ceremonies in the church's over-200-year history. LDS Church temples are different from the publicly accessible meetinghouses designated for weekly services, but rather are places restricted only to members in good standing with a recommendation from their leaders. Temples are considered highly sacred by LDS adherents. In these temples, they perform rituals, and are taught there that God has deemed temple ordinances as essential to achieving the theology's ultimate goal after death of exaltation. They are also instructed that a vast number of dead spirits exist in a condition termed spirit prison for whom when the temple ordinances are completed will have the option to accept these ordinances and be freed of their imprisonment. Temple ordinances are experienced by a living member of the Church for their own spiritual progression or vicariously on behalf of a deceased individual.