True philosophy must start from the most immediate and comprehensive fact of consciousness: 'I am life that wants to live, in the midst of life that wants to live'.
The Quest Of The Historical Jesus; A Critical Study Of Its Progress From Reimarus To Wrede[1], (1906), Augsburg Fortress Publishers, 2001 edition: ISBN 0-8006-3288-5
The Psychiatric Study of Jesus: Exposition and Criticism, (1911), Gloucester, Massachusetts: Peter Smith Publisher, 1948, ISBN 0-8446-2894-8
The Mystery of the Kingdom of God: The Secret of Jesus' Messiahship and Passion, (1914), Prometheus Books, 1985, ISBN 0-87975-294-7
The Decay and the Restoration of Civilization and Civilization and Ethics(1923)combined in one volume, Prometheus Books, 1987, ISBN 0-87975-403-6
The Mysticism of Paul the Apostle, (1930), Johns Hopkins University Press, 1998, ISBN 0-8018-6098-9
Out of My Life and Thought: An Autobiography(1933),Johns Hopkins University Press, 1998 edition with forward by Jimmy Carter: ISBN 0-8018-6097-0
Indian Thought and Its Development(1935)
Peace or Atomic War 1958
The Kingdom of God and Primitive Christianity(pub.1967)