Instruct: Classify Amazon reviews into positive or negative sentiment
Query: An excellent, handy quick reference

Trying to find out which Church council condemned Nestorianism? Need some background on Maximian of Ravenna or a quick history of the martyrdom of Perpetua and Felicitas? This volume is an excellent reference. Having used it as a resource for apologetical endeavors, I have found it supremely useful when confronted with historical personages or Christian teachings that were unfamiliar. Bibliographies at the end of each entry allow easy access to further research. I found two drawbacks: The first is regarding the large number of contributors - this ensures that the quality of the entries is somewhat uneven throughout. The second is the occasional 'political correctness' which creeps in to some entries - but I suppose that's unavoidable in a book published by a secular press. All in all, though, a very good reference.