The musical The Book of Mormon portrays two naïve Mormon missionaries in Uganda proclaiming that “in 1978, God changed his mind about black people.” The joke isn’t mere whimsy; the LDS Church is widely perceived as racist. The irony is that had the church followed its initial trajectory, by now it likely would have become the most racially integrated and progressive church in America.

Joseph Smith believed—as did most 19th-century whites—that black people were descendants of Cain. His views progressed, however, and when he died in 1844 he was running for U.S. president on an abolitionist platform. This platform quoted the Declaration of Independence on equality and “unalienable rights,” adding that “two or three millions of people are held as slaves for life, because the spirit in them is covered with a darker skin.”

A decade earlier, Smith ordained Elijah Abel, a biracial man, to the “Melchizedek priesthood” and showed kindness to a black household servant, Jane Manning James. He declared that “lynch law” would not do in Nauvoo, Illinois, and that “it is not right that any man should be in bondage one to another.”

But Smith died.

His successor, Brigham Young, was less open. Young proclaimed in 1852 that “the seed of Cain” could not be ordained in the priesthood.

After Young died in 1877, the question came up again. Young’s opinion was not set in stone, and there was no founding statement or “revelation” by Smith. When Elijah Abel asked in 1879 if he could receive his temple ordinances, a meeting was called to settle the priesthood question. Zebedee Coltrin, an aged man who made his living farming and giving patriarchal blessings, said that Smith had dropped Abel from the quorum once his race was discovered. Smith’s nephew, Joseph F. Smith, produced two certificates proving that Coltrin was wrong—and that Abel had twice been re-certified in his priesthood office.

One would think this would settle it. It didn’t. Abel was told he retained his priesthood—but he was denied entrance to the temple. Five years later he was dead, and there were few to tell his story. In 1908, Jane James also died, and her story with her. Months later, Joseph F. Smith reversed his own story about Abel and supported Coltrin’s.

From that point on, the priesthood restriction was a part of the LDS institutional memory—so entrenched that in 1949 the entire First Presidency signed a statement claiming that “Negroes...are not entitled to the priesthood” and never had been—by “direct commandment from the Lord.”

I was born six years later, the year Rosa Parks refused to give up her seat and Emmett Till was brutally murdered. I would learn of the civil rights movement from the distance of childhood. I would see Dr. King on the same television that showed George Reeves as Superman, and I would understand that we Mormons did not have blacks in our church.

I would not learn of Elijah Abel or Jane James until my twenties. I suspect most Mormons still don’t know who they were or how they could have shaped the church’s historical arc.

In 2012, however, the LDS Church was blessed by a blundering BYU professor who blithely explained to the Washington Post that before 1978, black people were unprepared for the priesthood. You wouldn’t give your car keys to your baby sister, would you? The church moved into defensive position, distancing itself from the prof.

He was already on my radar. In 1998 he disseminated a statement by 19th-century LDS president John Taylor explaining that God needs Satan and therefore “suffered the seed of Cain to come through the flood that Satan might have place on the Earth.” I asked to speak to the professor, suggesting that he possibly didn’t understand the implications of Taylor’s text. He responded that he often received questions about gospel doctrine but rarely received questions calling past prophets’ teachings into question.

With these words, he became my personal symbol of what the LDS Church faces: there is tremendous resistance to questioning the prophet, past or present. LDS members who are taught that they must “follow the prophet” because “he knows the way” often cling to old justifications for the priesthood restriction.

We are progressing. The church has condemned racism as a general principle. But the 1949 statement remains a stumbling block. The church has not yet repudiated the “curse of Cain” idea or other speculations that would allow us to justify ourselves in remaking God into a respecter of persons.

When we have returned to where we began; when leadership seats are filled with men and women of all complexions and ethnicities; when we have not only rejected past justifications for our racism but have actively worked to repair the damage we did to families and even to nations—then I’ll be happy to post an update. I anticipate this happening soon.

Our weekly feature Then and Now harnesses the expertise of American religious historians who care about the cities of God and the cities of humans. It's edited by Edward J. Blum.