Salt Lake City -- In his essay, "The Prophet Puzzle Revisited," author and historian Dan Vogel calls Joseph Smith, the founder of The Church of Jesus Christ of Latter-day Saints, complex and gifted.
He also says Smith was a "pious fraud," who knowingly duped followers into believing that God and angels spoke to him in visions, directing the formation of the church in 1830.
"I have no judgment as a historian upon what he did. What I like to talk about is what he thought he was doing," Vogel said in a telephone interview from his home in Westerville, Ohio. "And he thought he was doing a good work."
That work included writing the Book of Mormon, the faith's foundational text. Woven into its stories of battles between good and evil is the message that the Saints -- as Mormons are often called here -- should obey God's commandments and believe in Jesus Christ.
"Even if (the Book of Mormon) is not history, for Joseph Smith it's still inspired because it does those two things," said Vogel, a sixth generation Mormon who left the church about 30 years ago.
Mormons revere Smith as a true prophet, who through revelation restored God's true church to the earth. His life and work promise to be a central theme of the church's 175th semiannual conference here this weekend.
The two-day event will draw more than 100,000 to Salt Lake City, while millions more will observe the proceedings in more than 130 countries and 80 languages via television, satellite and radio broadcasts. The conference comes shortly before the 200th anniversary of Smith's birth on Dec. 23.
Whether prophet or fraud, that so many still focus on Smith's words and work is proof of the impact he has had on American religion.
When Smith was shot and killed -- believers say martyred -- in June 1844, the church had about 26,000 members. Today, there are more than 12 million Mormons around the world.
"He's significant because of the current believers," Vogel said, adding that many 19th century sects split from mainline Protestantism, only to fail. "If they didn't believe in him, he'd be irrelevant."
Mike Ash, is a self-described believing Latter-day Saint, who studies Mormon history and writes for FAIR, the Foundation for Apologetic Information and Research, which defends Mormon theology. He believes Smith endures because the church's core values and principles are grounded in truth.
"I've conversed with nonmembers and ex-members who still think that the (Mormon) church has good values," said Ash. "There's appreciation for that even if you don't accept Joseph Smith or Mormon theology."
But some critics dispute the idea that Smith's teachings have endured.
In the 14 years that Smith headed the church, its practices and philosophies changed frequently. And subsequent leaders, from Brigham Young to current President Gordon B. Hinckley have continued to shift the institution, said Sandra Tanner, a former Mormon who with her husband, Jerald, owns the Utah Lighthouse Ministry bookstore in Salt Lake City.
"I see them trying to downplay his teaching," said Tanner, whose own study and writings seek to debunk Mormon myths.
As evidence, Tanner cites a list of steps the church has taken away from Smith -- changes to sacred temple practices, the ordination of black men as priests, and the disavowal of plural marriage.
She also believes the church minimizes some aspects of Smith's theology -- for example, his ideas that God was once a human and that man himself can progress to become a god -- because they differ so much from mainline Christian ideals.
Susan Easton Black, a professor of religion at the church-owned Brigham Young University in Provo, Utah dismisses the criticism. Smith's later teachings represent his "deep conviction and deeper understanding," and an evolution of his theology, Black said. "The message is the same."
It's true that all religions and their leaders evolve, Salt Lake Theological Seminary associates professor Ron Huggins says.
"But the (Mormon) church is more prone to move away from Joseph Smith's teaching because it was so fluid in his life," Huggins said.
Black and Ash say Mormons expect change from their church, which believes in living prophets who continue to receive revelations from God.
"There wouldn't be a need for a prophet if you didn't expect that some things are going to change," Ash said. "I don't think Joseph received all the doctrine at once. He had to kind of assimilate that and synthesize that."
Nor does history hold Smith up as perfect.
"Joseph Smith has his weaknesses, as every man does," Ash said. "Through his journals, I consistently see he really believed in what he was doing and that he was very concerned for his fellow man."
Vogel believes Smith may have had genuine concern for others, but quickly adds that Smith knew how to take advantage of others.
"He exaggerated, enhanced and bent the truth to satisfy the need of his followers," Vogel said. "They call it spin nowadays."
Despite his beliefs, Vogel says he "can't answer whether (Smith) was a real prophet or not." But he and Ash agree that Smith is worthy of study and discussion, even if no definitive answers can be found.
"The past is gone and what the texts mean is not always clear," Vogel said. "They don't always provide answers. Sometimes it boils down to who has the best argument."