• Christ and Culture, H. Richard Niebuhr
• Christianity in the 21st Century: Reflections on the Challenges Ahead,
  Robert Wuthnow
• From Jesus to Christ, Paula Fredriksen
• The Gnostic Gospels, Elaine Pagels
• The Historical Figure of Jesus, E.P. Sanders
• The Historical Jesus, John Dominic Crossan
• A History of Christian Missions, Stephen Neill
• The New Testament: A Historical Introduction to the Early Christian Writings,
  Bart D. Ehrman
• The Orthodox Church, Timothy Ware
• The Oxford Illustrated History of Christianity, John McManners
• The Real Jesus: The Misguided Quest for the Historical Jesus, Luke T. Johnson
• The Reformation Theologians: An Introduction to Theology in the Early Modern Period, edited by Carter Lindberg
• The Story of Christianity, Justo Gonzalez
• Western Society and the Church in the Middle Ages, R.W. Southern
• World Christian Encyclopedia, David B. Barrett

Websites

• 10 Reasons to Believe, RBC Ministries
• Fides Quaerens Internetum (The Christian Theology Page),
  Bryan Stone, Boston University
• The Jesus Seminar Forum, Jesus Seminar
• The Orthodox Page in America, Michael Vezie
• Protestant Denominations, Gene Thursby, University of Florida
• Theology Library at Spring Hill College [Catholic Resources],
  Gerald Darring, Spring Hill College