'The reading of Systematic Theology can be a great voyage of discovery into a rich and deep, an inclusive and yet elaborated, vision and understanding of human life in the presence of the mystery of God' (H. Richard Niebuhr). 'The real intent and accomplishment of Dr Tillich is to show that the full truth of human existence can only be grasped through a meeting and ultimately a uniting of personal faith and rational understanding. He is interpreting the Christian faith to the mind of twentieth-century man with such penetration that the self-understanding both of the secular culture and of the Christian church is being deepened and clarified' (Daniel Day Williams). ' 'Tillich's Systematic Theology is beyond doubt the richest, most suggestive and most challenging philosophical theology our day has produced' (Journal of Religion).