Johann and Margarethe joined the LDS Church in 1903, and the local congregation held meetings in the family's home.
Schreiner first performed on an organ professionally during the fall of 1917 at the American Theater of Salt Lake City.
[4] In 1920, just after graduating from high school, he took a job as a theater organist at the Rialto Theatre in Butte, Montana.
In 1924, just after returning from his mission, Schreiner was appointed an assistant organist of the Salt Lake Mormon Tabernacle.
[7] Six months later Schreiner took a leave of absence from this appointment to go to Paris to further his musical studies[8] with Henri Libert, Charles-Marie Widor and Louis Vierne.
[11] After his studies in France, Schreiner returned to his position as organist in Salt Lake City from July 1926 to January 1927.
He then went to southern California to earn enough money to pay off his debts and be in a position to marry Margaret.
During this time period Schreiner also worked as an organist at the Barker Brother's Department Store.
[14] Schreiner returned to Salt Lake and the Tabernacle in the summer of 1930, but in September 1930 he began a term as the organist of the University of California at Los Angeles (UCLA).
Schreiner wrote the music to the following hymns in the 1985 English edition of the Latter-day Saint hymnal: Some of his writings refer specifically to his association with the Tabernacle organ such as the following: ,