Peter J. Leithart (PhD, University of Cambridge) is president of Theopolis Institute and the author of many books, including Defending Constantine, Delivered from the Elements of the World, Baptism, and On Earth as in Heaven. Ordained in the Communion of Reformed Evangelical Churches (CREC), Dr. Leithart has pastored Reformed Heritage Presbyterian Church (now Trinity Presbyterian Church) in Birmingham, Alabama, and Trinity Reformed Church in Moscow, Idaho. He and his wife, Noel, have ten children and fifteen grandchildren.

Tara Leithart is the secretary at Immanuel Reformed Church. She and her husband Christian have two children.