As of Friday, Dec. 6, the Mormon Church has officially renounced the doctrine that brown skin is a punishment from God.

In the “Book of Mormon,” (not the musical but the actual sacred text) dark skin is a sign of God’s curse, while white skin is a sign of his blessing. The book tells of a conflict between two lost tribes of Israel, the Lamanites and Nephites, who journeyed to the New World and made their home in Mesoamerica. The Lamanites sinned against God, and “because of their iniquity. …the Lord God did cause a skin of blackness to come upon them” (2 Nephi 5:21). Later, when Lamanites became Christians, “their curse was taken from them, and their skin became white like unto the Nephites” (3 Nephi 2:15).

These verses were thought to explain the dark skin of Native Americans. In 1960, Church apostle Spencer W. Kimball suggested at the general conference that Native Americans who converted to Mormonism were gradually becoming lighter skinned:

I saw a striking contrast in the progress of the Indian people today… The day of the Lamanites is nigh. For years they have been growing delightsome, and they are now becoming white and delightsome, as they were promised. In this picture of the twenty Lamanite missionaries, fifteen of the twenty were as light as Anglos, five were darker but equally delightsome. The children in the home placement program in Utah are often lighter than their brothers and sisters in the hogans on the reservation. At one meeting a father and mother and their sixteen-year-old daughter we represent, the little member girl—sixteen—sitting between the dark father and mother, and it was evident she was several shades lighter than her parents—on the same reservation, in the same hogan, subject to the same sun and wind and weather… These young members of the Church are changing to whiteness and to delightsomeness.

The blackness of Africans derived from an even more ancient stain, Cain's murder of his brother Abel in the Genesis story.

Joseph Smith taught that black people are cursed as “sons of Cain” but also could be saved. Brigham Young, his successor, was harsher: “Shall I tell you the law of God in regard to the African race? If the white man who belongs to the chosen seed mixes his blood with the seed of Cain, the penalty, under the law of God, is death on the spot. This will always be so” (Journal of Discourses, vol. 10). Since dark skin was a divine punishment for sin (rather like Eve's curse, which causes women to suffer in childbirth), black men could not be ordained into the priesthood of the LDS church, a designation open to any white male age 12 and older who is "morally upright."

During the Civil Rights Movement, the LDS Church came under pressure as such teachings became offensive to a growing number of people. Simultaneously, the church expanded its missionary efforts into Brazil where almost everyone has some slave ancestors. How pureblooded did a light-skinned man have to be to receive ordination or enter the temple? In this context, Spencer Kimball, who was now Church president, announced a new revelation in 1978, and black men were granted the priesthood. But in Mormon sacred texts, the old racism remained.

Over the years, ordinary Mormons and church leaders have struggled with this heritage. One racist passage in the scripture—2 Nephi 30:6 —has simply been fixed by Mormon authorities. Originally reading that conversion to Christianity creates a “white and delightsome people,” in 1981 the Church adopted a variant that now reads, “a pure and delightsome people.” (Joseph Smith had used each of the phrases.)

Now, with 2013 winding down, Church authorities have decided to tackle the problem head-on. In a 2000 word document posted Friday, officials emphatically renounced the racist teachings of the past:

The church disavows the theories advanced in the past that black skin is a sign of divine disfavour or curse, or that it reflects actions in a premortal life; that mixed-race marriages are a sin; or that blacks or people of any other race or ethnicity are inferior in any way to anyone else. Church leaders today unequivocally condemn all racism, past and present, in any form.

Much of what is in the new document has been said before by Mormon scholars attempting to reconcile modern ethics with Church history. But this new statement is noteworthy because it comes from the Church headquarters in Salt Lake City. Unlike many other forms of Christianity, the Mormon hierarchy maintains strict control over doctrinal evolution and public statements. A group called the “Correlation Committee” carefully reviews official documents and even Sunday school curricula to ensure consistency in teachings, emphasis and tone. Consequently, this document can be seen as part of an official trend toward greater openness and transparency about Mormon history.

Increasingly, Mormon authorities are adopting the stance that the best way to meet criticism is with good humor and well-framed candor. After expressing big disapproval over “Big Love,” Church leaders shifted strategies and met the hit musical, the "The Book of Mormon," with bemused acceptance, praising it "for really nailing the Mormon sweetness, niceness, and sense of do-gooderness." They filled theater programs with their own advertisements.

Thanks to a number of factors, including the Romney presidential run, Mormons see an opportunity to move from being perceived as a fringe “cult” to being recognized as a thread in the tapestry of Christianity. In an effort to reassure evangelical voters during his presidential candidacy, Mitt Romney inserted the phrase “the same god” into his domestic policy debate against Barack Obama. Church leaders have since issued a communiquÃ© addressing the question of whether Mormons are Christians (answer: yes). Even some LDS quirks seem to be turning into positives. Shifting sexual mores have made Mormon polygamy and sacred undergarments a matter of slightly kinky fascination rather than Puritan disgust.

Friday’s document from Mormon headquarters explains even the Church’s history of racism in terms that say, “we are simply part of American culture”:

The Church was established in 1830, during an era of great racial division in the United States. At the time, many people of African descent lived in slavery, and racial distinctions and prejudice were not just common but customary among white Americans. Those realities, though unfamiliar and disturbing today, influenced all aspects of people’s lives, including their religion.

Efforts to mainstream Mormon religion are taking many forms. Over the course of 2012, the LDS Church promoted “I’m a Mormon,” a multi-million dollar marketing campaign about ordinary Americans who are also ordinary Mormons. The Church is reaching out to young people, and the current emphasis on civil rights can be seen as one strong way of allying with youth culture. That said, as former Mormon Garrett Amini explains, getting the Mormon hierarchy to embrace other civil rights like real equality for women and gays may present an even bigger theological challenge than equality for blacks.

Also, the question of whether Mormon beliefs will be accepted as mainstream has challenges of its own. Per Amini, materials approved by the Correlation Committee “have significantly de-emphasized the more controversial doctrines in recent years.” Dr. Tony Nugent, retired professor of religious studies, agrees. In 2012, Nugent compiled a list of twelve teachings that Mormon authorities tend to downplay, each of which is, in one way or another, dubious. A quick read suggests they also are far from mainstream.

With Friday’s clear and authoritative repudiation of racism, the list is down to eleven. May the process of wrestling and growth continue.