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Source:Church History In The Fulness Of Times Student Manual:2003:The law of celestial marriage, as outlined in this revelation, also included the principle of the plurality of wives
Church History in the Fulness of Times (2003): "The law of celestial marriage, as outlined in this revelation, also included the principle of the plurality of wives"
Institute Manual: Church History in the Fulness of Times:
Later that summer Joseph recorded a revelation on marriage that incorporated principles that had been revealed to him as early as 1831 in Kirtland. In it the Lord declared, “If a man marry a wife by my word, which is my law, and by the new and everlasting covenant, and it is sealed unto them by the Holy Spirit of promise, by him who is anointed, unto whom I have appointed this power and the keys of this priesthood . . . [it] shall be of full force when they are out of the world; and they shall pass by the angels, and the gods, which are set there, to their exaltation and glory in all things, as hath been sealed upon their heads, which glory shall be a fulness and a continuation of the seeds forever and ever” ( D&C 132:19 ).
The law of celestial marriage, as outlined in this revelation, also included the principle of the plurality of wives. In 1831 as Joseph Smith labored on the inspired translation of the holy scriptures, he asked the Lord how he justified the practice of plural marriage among the Old Testament patriarchs. This question resulted in the revelation on celestial marriage, which included an answer to his question about the plural marriages of the patriarchs.
First the Lord explained that for any covenant, including marriage, to be valid in eternity it must meet three requirements (see D&C 132:7 ): (1) It must be “made and entered into and sealed by the Holy Spirit of promise.” (2) It must be performed by the proper priesthood authority. (3) It must be by “revelation and commandment” through the Lord’s anointed prophet (see also vv. 18–19 ). Using Abraham as an example, the Lord said he “received all things, whatsoever he received, by revelation and commandment, by my word” ( v. 29 ). Consequently, the Lord asked, “Was Abraham, therefore, under condemnation? Verily I say unto you, Nay; for I, the Lord, commanded it” ( v. 35 ).
Moreover, Joseph Smith and the Church were to accept the principle of plural marriage as part of the restoration of all things (see v. 45 ). Accustomed to conventional marriage patterns, the Prophet was at first understandably reluctant to engage in this new practice. Due to a lack of historical documentation, we do not know what his early attempts were to comply with the commandment in Ohio. His first recorded plural marriage in Nauvoo was to Louisa Beaman; it was performed by Bishop Joseph B. Noble on 5 April 1841. 12 During the next three years Joseph took additional plural wives in accordance with the Lord’s commands.
As members of the Council of the Twelve Apostles returned from their missions to the British Isles in 1841, Joseph Smith taught them one by one the doctrine of plurality of wives, and each experienced some difficulty in understanding and accepting this doctrine. 13 Brigham Young, for example, recounted his struggle: “I was not desirous of shrinking from any duty, nor of failing in the least to do as I was commanded, but it was the first time in my life that I had desired the grave, and I could hardly get over it for a long time. And when I saw a funeral, I felt to envy the corpse its situation, and to regret that I was not in the coffin.”
After their initial hesitancy and frustration, Brigham Young and others of the Twelve received individual confirmations from the Holy Spirit and accepted the new doctrine of plural marriage. They knew that Joseph Smith was a prophet of God in all things. At first the practice was kept secret and was very limited. Rumors began to circulate about authorities of the Church having additional wives, which greatly distorted the truth and contributed to increased persecution from apostates and outsiders. Part of the difficulty, of course, was the natural aversion Americans held against “polygamy.” This new system appeared to threaten the strongly entrenched tradition of monogamy and the solidarity of the family structure. Later, in Utah, the Saints openly practiced “the principle,” but never without persecution. 
The number of dissenters in Nauvoo grew with the addition of Church members who opposed plural marriage and other new doctrines taught by Joseph Smith. William Law, second counselor in the First Presidency, his brother Wilson Law, major general in the Nauvoo Legion, and high council members Austin Cowles and Leonard Soby all believed that Joseph Smith was a fallen prophet. 
The Twelve were among the first to receive instruction from Joseph Smith on plural marriage and the temple ordinances. 
A large part of the persecution experienced by the Latter-day Saints centered around the practice of plural marriage, which was instituted under the direction of the Prophet Joseph Smith. The law of plural marriage was revealed to the Prophet as early as 1831, but he mentioned it only to a few trusted friends. Under strict commandment from God to obey the law, the Prophet began in 1841 to instruct leading priesthood brethren of the Church concerning plural marriage and their responsibility to live the law. The Prophet Joseph Smith dictated the revelation to William Clayton in 1843, when it was first written. Nine years passed, however, before the revelation was read in general conference and published. 
- "Chapter Twenty: Doctrinal Developments in Nauvoo," Church History In The Fulness Of Times Student Manual, (2003).
- "Chapter Twenty One: Growing Conflict in Illinois," Church History In The Fulness Of Times Student Manual, (2003).
- "Chapter Twenty-Three: The Twelve to Bear Off the Kingdom," Church History In The Fulness Of Times Student Manual, (2003)
- "Chapter Thirty-Three: A Decade of Persecution, 1877–87," Church History In The Fulness Of Times Student Manual, (2003).