 Halverson was a minister of the former United Presbyterian Church in the United States of America and served from 1958 until 1981 as the Senior Pastor of the Fourth Presbyterian Church, in Bethesda, Maryland.He served as the Chaplain of the United States Senate from February 2, 1981 until March 11, 1995.He was an associate of the National Prayer Breakfast movement starting in 1956 along with Bill Bright and Douglas Coe.