After quoting from 2 Nephi 29 and Alma 29, the LDS leader and historian B. H. Roberts wrote:

“This is the Mormon theory of God’s revelation to the children of men. While the Church of Jesus Christ of Latter-day Saints is established for the instruction of men, and is one of God’s instrumentalities for making known the truth, yet he is not limited to that institution for such purposes, neither in time nor place.

God raises up wise men [and women] and prophets here and there among all the children of men, of their own tongue and nationality, speaking to them through means that they can comprehend…

“Mormonism holds, then, that all the great teachers are servants of God; among all nations and in all ages. They are inspired men, appointed to instruct God’s children according to the conditions in the midst of which he finds them.

“Hence it is not obnoxious to Mormonism to regard Confucius, the great Chinese philosopher and moralist, as a servant of God, inspired… by him to teach those great moral maxims which have governed those millions of God’s children for lo! these many centuries.

“It is willing to regard Gautama, Buddha, as an inspired servant of God, teaching… the truth…

“So with the Arabian prophet [Muhammad], that wild spirit that turned the Arabians from worshiping idols to a conception of the Creator of heaven and earth that was more excellent than their previous conception of Deity.

“And so the sages of Greece and of Rome.

“So the reformers of early Protestant times.

“Wherever God finds a soul sufficiently enlightened and pure; one with whom his Spirit can communicate, lo! he makes of him a teacher of men.

“While the path of sensuality and darkness may be that which most men tread, a few, to paraphrase the words of a moral philosopher of high standing, have been led along the upward path; a few in all countries and generations have been wisdom seekers, or seekers of God.

They have been so because the Divine Word of Wisdom has looked upon them, choosing them for the knowledge and service of himself…

“…it is nowhere held that [the Church’s Prophet] is the only instrumentality through which God may communicate his mind and will to the world.”

—B. H. Roberts, Defense of the Faith and the Saints (1907), 512–13.

Also recently quoted in part on 13 October 2017 by the LDS Church Newsroom in its article “Treasuring All Truth.”