What is THE most valuable reference book you own?

Many people who are interested in apologetics have lots of religious reference books. But suppose you could keep only ONE. Which would it be?

(And I don’t think of the Bible as a “reference book,” so I’m not talking about the Bible here)

I’ll go first: The Oxford Dictionary of the Christian Church. I have an older Second Edition. The Third Edition was considerably expanded, and apparently a Fourth Edition just came out in January. It ain’t cheap ($125 on Amazon) but worth *every *penny, IMHO.

I own the Anchor Bible Dictionary. I guess that’s not just one book, though.

Catechism of the Catholic Church, and if that is not considered a reference, Denzinger’s “Sources of Catholic Dogma”, the Catholic Enclyclopedia or my set of The Great Books of the Western World. Thanks and God Bless.

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