He was baptized by Lyman E. Johnson and soon afterwards ordained to the Priesthood and called into the mission field.
Called on a mission March 12, 1833, he labored in New York, etc., with William F. Cahoon as a companion. Journal History of Mar 23, Apr 16, May 1, 1833
Volunteered his services as a missionary Aug. 6 1834; Horace Cowan was appointed to labor with him. Journal History of Aug. 6, 7, 1834
Traveling from Clay county, Missouri, to Kirtland, Ohio, preached the Gospel on the way and held many meetings.
D&C 124:136 at Nauvoo, Illinois.
Called at a general conference of the Church held at Nauvoo, Illinois, April 9, 1841, to travel extensively to collect means for the building of the Nauvoo temple.
To preside with George P. Dykes over the twenty three missionaries sent to assist Joseph Smith's presidential campaign and preach the gospel in Indiana. (History Journal, April 15, 1844, p. 2)
Called as a missionary to the Emmett's Company.
Amasa made several trips across the plains. He traveled to the Valley for the first time with the 1847 Brigham Young Company and was part of the 2nd Company of Ten led by Ezra Taft Benson. He left the company on 3 June at Fort Laramie to take a message to the Mormon Battalion sick detachments and Mississippi Saints at Pueblo, Colorado.
Was a returning missionary
Called to San Francisco to oversee the California branches & collect tithing; then lead a company of California Saints to the valley in the fall.
As a returning missionary he crossed the plains again in 1866 with the Daniel Thompson company. His name appears on company records, but it is unclear if the notation indicates that he was actually present, or if the company was simply carrying freight that was to be delivered to him.
