Account in An Original History of the Religious Denominations at Present Existing in the United States, edited by Daniel Rupp. Joseph Smith wrote the chapter on Mormonism.
Joseph Smith, Latter Day Saints, pages 404-405
“When about fourteen years of age, I began to reflect upon the importance of being prepared for a future state; and upon inquiring the place of salvation, I found that there was a great clash in religious sentiment; if I went to one society they referred me to one place, and another to another; each one pointing to his particular creed as the "summum bonum" of perfection. Considering that all could not be right, and that God could not be the author of so much confusion, I determined to investigate the subject more fully, believing that if God had a church, it would not be split up into factions, and that if he taught one society to worship one way, and administer in one set of ordinances, he would not teach another principles which were diametrically opposed. Believing the word of God, I had confidence in the declaration of James, "If any man lack wisdom let him ask of God, who giveth to all men liberally and upbraideth not, and it shall be given him."
I retired to a secret place in a grove, and began to call upon the Lord. While fervently engaged in supplication, my mind was taken away from the objects with which I was surrounded, and I was enrapt in a heavenly vision, and saw two glorious personages, who exactly resembled each other in features and likeness, surrounded with a brilliant light, which eclipsed the sun at noonday. They told me that all the religious denominations were believing in incorrect doctrines, and that none of them was acknowledged of God as His Church and Kingdom. And I was expressly commanded to "go not after them," at the same time receiving a promise that the fullness of the gospel should at some future time be made known unto me."