There are a group of inquirers into Christianity who have traveled various paths through perennial philosophy - coming through sufis, kabbalah, theosophy, zen, ... I would like to see some resources on the perennial philosophy tradition so that I can learn best how to approach these inquirers to convince them of the unique position of Christianity. These books from the Library of Perennial Philosophy might serve as a starting point:
Other potential works that come to my mind:
Note I have purposely focused on the stream of perennial philosophy that has the most Christian and Islamic input rather than a representative sample.
