The Kingdom of God, part 1

 Orson Pratt was the younger brother of Parley P. Pratt, who introduced him to the Church of Jesus Christ of Latter Day Saints and baptized him on his nineteenth birthday, September 19, 1830 in Canaan, New York.

Pratt was ordained an Elder several months later, on April 26, 1831, by the Prophet Joseph Smith, Jr. and immediately set out for Colesville, New York, his first mission. This was the first of a number of short missions in which Orson visited New York, Ohio, Missouri, and the Eastern States. On February 2, 1832, he was ordained a High Priest by Sidney Rigdon, whereafter he continued his missions, preaching in Pennsylvania, New York, New Jersey, Vermont, New Hampshire, Connecticut, and Massachusetts.

Orson Pratt was a member of the original Quorum of the Twelve Apostles under Joseph Smith.  He was ordained to this position on April 26, 1835. He served as a member of the mission of the Twelve Apostles to the British Isles between 1839 and 1841. He contributed to the mission by preaching in Scotland, and producing an early missionary tract, An Interesting Account of Several Remarkable Visions. This tract contains the earliest known public printing of an account of Joseph Smith's First Vision and also contains material similar to that later published as the 1842 Articles of Faith.