After graduation (and the birth of his first child) Roberts was ordained a seventy in his local church branch and taught school to support his family.

The LDS Church sent him on a mission to Iowa and Nebraska, "but because the cold weather was hard on his health, he was transferred to Tennessee in December of 1880."

[3] In England, Roberts served as assistant editor of the LDS Church publication the Millennial Star and completed his first book, the much reprinted The Gospel: An Exposition of Its First Principles (1888).

Returning to Salt Lake City in 1888, as full-time editor of The Contributor, he was chosen as one of the seven presidents of the First Council of the Seventy, the third-highest governing body in the LDS Church.

Following his release, he moved his families to Colorado and married a third wife, Dr. Margaret Curtis Shipp, after[9] church president Wilford Woodruff issued the 1890 Manifesto that prohibited solemnization of new plural marriages.

[11] He resigned as an editor of the Salt Lake Herald in 1896, giving his reason that the position that the paper had taken on the recent "Manifesto" was apt to place him in a false light.

The age limit of forty was waived—Roberts was then sixty—and Roberts became chaplain to the 145th Field Artillery, which arrived in France in September 1918 but did not see action before the Armistice was signed in November.

[17] In the late 1890s, he also helped establish the Improvement Era and became the de facto editor of this official periodical of the LDS Church.

It was later adapted, along with A Ship of Hagoth by Julia MacDonald, into a play by Orestes Utah Bean,[22] and was the inspiration for the 1931 film Corianton: A Story of Unholy Love.

Roberts's most important work was a comprehensive treatment of Mormon history, which he began in 1909 as a series of monthly articles for a non-Mormon magazine.

The six-volume Comprehensive History of the Church of Jesus Christ of Latter-day Saints: Century I (3,459 pages) covered for the first time many late-19th- and early-20th-century developments.

Roberts' theology included belief in "the modern liberal doctrine of man and the optimism of the nineteenth century, and it required a bold, rebellious and spacious mind to grasp its full implication.

"[24] Roberts hoped that the church would publish his most elaborate theological treatise, "The Truth, The Way, The Life", but his attempt to use contemporary scientific theory to bolster Mormon doctrine led, in 1930, to a conflict with Mormon apostle Joseph Fielding Smith, who had been influenced by the writings of young earth creationist George McCready Price.

Smith publicly opposed Roberts's quasi-evolutionary views in deference to a literal reading of both the Bible and the Latter-day Saint scriptures.

[25] The controversy was debated before the Quorum of the Twelve Apostles, and it "declared a draw: Neither the existence nor the nonexistence of pre-Adamites would constitute church doctrine.

The first, "Book of Mormon Difficulties: A Study," was a 141-page manuscript written in response to a series of questions by an inquirer, referred to Roberts by church president Heber J.

In this work he compared the Book of Mormon to the View of the Hebrews (1823), written by Ethan Smith, which argued Native Americans were descendants of the Ten Lost Tribes of Israel.

"[32] Roberts continued to affirm his faith in the divine origins of the Book of Mormon until his death in 1933; but as Terryl Givens has written, "a lively debate has emerged over whether his personal conviction really remained intact in the aftermath of his academic investigations.

Regardless of his ultimate religious beliefs, most scholars would accept the judgment of Brigham Madsen that Roberts possessed a "deeply embedded integrity, and above all ... fearless willingness to follow wherever his reason led him.