He became a member of the Quorum of the Twelve Apostles on April 9, 1953, filling a vacancy created by the death of John A. Widtsoe.

[1] After their marriage, Bennion and his wife headed to New York City, where he completed a master's degree at Columbia University.

Bennion returned to Salt Lake City and became an English teacher at Granite High School.

The following year, he was appointed a member of the General Board of the Deseret Sunday School Union.

[2] In 1944, Bennion resigned his employment with UP&L and ran as a Republican Party candidate for the United States Senate.

In 1953, LDS Church president David O. McKay called Bennion as a member of the Quorum of the Twelve Apostles.