A path breaking collection of essays on the phenomenon of unio mystica in Judaism, Christianity, and Islam. The authors all major authorities penetrate to the heart of their subject and show the shapes and types of unitive mystical experience in these major monotheistic faiths. Particularly important are the considerations of the formative power of language in the mystical experience generally and a consideration of some psychological dimensions. Concluding comments by the authors are a model of reflective scholarly discourse. The book is a master text in the comparative study of mysticism.