John graduated from the Naval Academy and served in the Marine Corps in Okinawa, before being called to the ordained ministry. He graduated from Virginia Theological Seminary (VTS) in Alexandria, Virginia, and served in a parish in Washington, DC. where he met his wife-to-be, Blanche Kostka. Blanche came from a Czech community in Nebraska and was working in the city while pursuing graduate studies at American University. The couple were married in 1959 and moved shortly thereafter to Basel, Switzerland, where John earned his Doctor of Theology degree, studying with the renowned theologian Karl Barth.

John and Blanche returned to VTS in 1963. During his thirteen years there, they raised four children. John became a popular Professor of Systematic Theology and was known throughout the Anglican Communion as one of its foremost Evangelical theologians. He worked alongside the Rev. Dr. Fitzsimons Allison and other orthodox faculty to defend traditional Christian doctrine.

In 1976, John left VTS to join the pioneer faculty of Trinity Episcopal School for Ministry in Ambridge, Pennsylvania, which grew out of the Evangelical and charismatic renewal movements. For the next 20 years John taught theology to students at Trinity, occasionally breaking into song while lecturing, as well as serving as Dean/President from 1978 to 2000. Under his leadership, Trinity grew to become a major seminary in the Episcopal Church. For a short time in the early 1990s, he also served as the rector of St. Stephen's Church, Sewickley.

In the late 1990s John wrote a confessional statement, "A Place to Stand, A Call to Mission", the foundation to the First Promise movement, and in 2000, he was consecrated a bishop in South East Asia to begin The Anglican Mission in America, helping US churches stay connected to The Anglican Communion. John also spoke at the international Global Anglican Future Conference in Jerusalem in 2008 while he was acting as interim Dean/President at Trinity again. In addition to his books on the 39 Articles, John participated in a series of interviews with his long-time friend the Rev. Dr. Stephen Noll published as "Zoom Memoirs" in 2021. John was, many observed, a "happy warrior" while standing firm for Biblical orthodoxy.

In 2006, John and Blanche moved to a retirement village and after Blanche's death in August 2020 John wrote: "I miss her more than I can put into words. I look forward to the day when I will be with her and all our loved ones in the New Heaven and Earth." Now his wish has been granted.

John was an outstanding 3-point basketball player, talented ping-pong competitor, Louis L'Amour aficionado, loved a good cup of coffee and watching all sports, especially his beloved Steelers. John and Blanche are survived by their four children, Mark (Leanne), Sarah (Curtis), Martha (Paul) and Paul (Lauren), eleven grandchildren and five great grandchildren. His family remember him for his generous spirit, joyful heart, and steadfast devotion to his wife and to his beloved Savior Jesus Christ.

A memorial service will be held in 2023 at St. Stephen's Church, Sewickley. In lieu of flowers, John and the family suggest that contributions be made to Trinity School for Ministry, 311 11th St, Ambridge, PA 15003.