The Book of Ceremonial Magic

The Book of Ceremonial Magic by Arthur Edward Waite was originally called The Book of Black Magic and of Pacts. It is an attempt to document various famous grimoires, explain the history behind them (refuting many of the legends surrounding them), discuss the theology contained therein (e.g. raising the question why good angels would be summoned to kill an enemy), and to synthesize many famous grimoires into one system.