Mormon church leaders describe it as a shared, simultaneous revelation from God.
The moment happened 25 years ago, as the church's top leaders the three-man First Presidency and the Quorum of the Twelve Apostles gathered inside the faith's Salt Lake City Temple.
The officials say God revealed to them that the church should change its practice of more than a century and allow black men to become members of the Mormon priesthood, which has always been open to those of other races.
The church ended the ban with a four-paragraph statement released on June 8, 1978. It began with a reference to the church's global growth and simply said "every faithful, worthy man in the Church may receive the holy priesthood."
Since then, The Church of Jesus Christ of Latter-day Saints has grown significantly in Africa, Brazil and the Caribbean. A church-sponsored organization for black Mormons has several events planned to commemorate the anniversary this weekend.
But some black Mormons in America still feel the church doesn't do enough to encourage black membership, or speak out against racism of the past.
Tamu Smith, a black member of the church in Provo, Utah, said she thinks that's caused by concern about how some whites within the church might respond.
"They've spoken directly to certain issues in the past, they speak directly about homosexuality, adultery, pornography ... They have not spoken directly against prejudice and racism," said Smith, who remembers being insulted with a racial slur during a visit to the Salt Lake temple with her white husband and his aunt in 1993.
The issue is a thorny one for the church.
Mormons believe their president the leader of the First Presidency is a "living prophet" who rules by direct divine revelation, so the black priesthood ban must be seen as God's will or else the divine prophets from the mid-19th century until 1978 were grievously mistaken.
"The reason they've held off issuing a denunciation, I think, it is the fact that it would look poorly on" those past leaders, said Newell Bringhurst, a history and government professor at the College of Sequoias, in Visalia, Calif.
The Mormon priesthood does not refer to a set of trained clerics, rather it is a lay status that virtually all Mormon boys enter at 12. It is the prerequisite for even the most mundane church responsibilities.
The first black man to hold the priesthood, Elijah Abel, was ordained in 1836 by church president and founder Joseph Smith. The modern church acknowledges the status of Abel, who was honored with a monument at the Salt Lake City Cemetery dedicated last fall.
What happened between the days of Smith, who also spoke out against slavery decades before the Civil War, and the revelation of 25 years ago is a matter of debate.
Baptism and membership in the church have always been open to all. But starting in roughly the late 1840s, black males were denied the priesthood "for reasons that we believe are known to God," church spokesman Dale Bills said.
Bringhurst, who was raised Mormon but has since left the church, has examined the question as part of his extensive research and writing about racial issues among Mormons.
He attributes the ban to remarks made by Brigham Young, the church's president after Smith was assassinated in Nauvoo, Ill.
Young once said that blacks were the children of Cain who settled in Africa, and "any man having one drop of the seed of Cain" could not gain priesthood. Bringhurst says that view took hold.
A century later, the ban came under increasing scrutiny during the civil rights era. In a 1966 book, Wallace Turner of The New York Times called the LDS Church "one of the most influential organs of racial bigotry in the United States."
Still, Bringhurst said the church's international expansion more likely prompted its review of black priesthood.
According to a 1988 interview with Ensign magazine, church President Gordon B. Hinckley a member of the First Presidency at the time of the revelation described the event as feeling "as if a conduit opened between the heavenly throne and the kneeling, pleading prophet of God."
In the decades following the revelation, the number of African members of the LDS has gone from around 12,000 to more than 180,000.
But Natalie Sheppard, a black American who joined the church 20 years ago, says she's never felt the church has done a good job of encouraging black membership. She felt that particularly keenly when she moved from Ohio to a Salt Lake City suburb.
"When I came here I experienced the rudest awakening of my life," Sheppard said.
She recalled storming into church headquarters on a cold day in 1982, after her 6-year-old son was made to stand outside the home of another church member while waiting for her to pick him up because he was black.
Sheppard got to see a group that included Ezra Taft Benson, a future church president.
"They took me into this room lined with men in black suits. In my anger I did not appreciate the audience I had," Sheppard said. "Ezra Taft Benson said, 'If you joined the church for the people in the church you didn't join the church for the right reasons.'"
Sheppard was satisfied, but she now understands why other black members are hungry for stronger church statements against perceived lingering racism and the words of past leaders.
Sheppard once held a position with the Genesis Group, an organization for black Mormons, that allowed her to meet with inactive black members who felt the church didn't want to fully address racism.
"I'm not saying that people need to apologize," Sheppard said, "but we lose a lot of black members."
This weekend, Genesis is commemorating the 1978 revelation by sponsoring several events, including performances of the play "I Am Jane," the story of Jane Elizabeth Manning James, a black woman who was an active member of the church and traveled with Mormon pioneers in the late 1840s.
On Sunday, the actual anniversary, singer Gladys Knight one of the church's best-known black converts will conduct the Saints Unified Voices, a 110-person multiracial choir.
"This commemoration is an expression of great growth and it comes with the promise of great hope," said Darius Gray, president of Genesis and author of a three-book series examining the history of blacks in the church. "I am happy. The world changed 25 years ago and those changes are just under way."