Very thoughtful ...

... and very worth reading: The Ground of Being. (Hat tip, Dave Lull.)

Another book worth reading in this connection is Rudolf Otto's The Idea of the Holy. My own experience suggests to me that it is easier to explain the Eucharist to an Inuit than it is to explain it to a Manhattan secularist, principally because the Inuit probably does have some idea of the holy.

One final thought: The three most insightful notions regarding transcendence that I can think of are the I Am Who Am of Exodus, Heraclitus' notion of the Logos, and Lao-tse's concept of the Tao. All have much in common and all take us beyond locally circumscribed theologies.