THIS study of the nature and principles of Worship, and the chief forms in which they find expression in Christianity, is not the work of a liturgical expert, and is not intended as a handbook to that difficult science. My object has been rather to explore those primary realities of man’s relation to God which our devotional action is intended to express. Worship is here considered in its deepest sense, as the response of man to the Eternal: and when we look at the many degrees and forms of this response, and the graded character of human religion, its slow ascent from primitive levels and tendency to carry with it the relics of its past, we need not be surprised that even within the Christian family there is much diversity in the expressive worship which is yet directed towards a single revelation of the Divine.