Mormon leaders have admitted for the first time that the church's founder, Joseph Smith, took multiple wives, some of whom were in their early teens or married to other men.

The Salt Lake Tribune reports that the essay disclosing Smith's polygamy was posted on the official website of The Church of Jesus Christ of Latter-day Saints late last months. The essay was posted alongside an earlier offering detailing the history polygamy in Utah, where most Mormons live.

The work is part of a series of essays posted by the Mormon church about several topics that have made the faith a subject of controversy, including a ban on blacks in the priesthood that was not lifted until 1978,

The essay does not give a specific number of wives Smith had, but researcher Todd Compton told the Tribune that he believed the number to be at least 33, with 10 of those women under the age of 20. One of the women, Helen Mar Kimball, the daughter of two of Smith's close friends, was 14 at the time of their marriage.

The church claims that Smith likely did not have sexual relations with all his wives, but rather reserved, or "sealed", some relationships for the afterlife. The essay also claims that the practice of polygamy was revealed to Smith during his study of the Old Testament in 1831 and accepted reluctantly by the church's founder and a select group of his cohorts.

Smith was killed by a mob in Nauvoo, Illinois in 1844 at the age of 38. He was survived by his first wife, Emma, who lived until 1879. The essay claims that Emma "approved, at least for a time, of four of Joseph Smith’s plural marriages," but later "vacillated in her view of plural marriage, at some points supporting it and at other times denouncing it."

Polygamy was not formally forbidden by the church until 1890, under pressure from the U.S. government. Even after the issuance of a manifesto, the practice continued, with some who refused to renounce it forming splinter churches. Mormons still believe that a man whose wife has died or divorced him can remarry and then be "sealed" to both wives in the afterlife.

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