Even heaven has had a war. " And there was war in heaven: Michael and his angels fought against the dragon; and the dragon fought and his angels " (Revelation 12:7).

“The War in Heaven,” Mr. Jacobs quips, was “recapitulated as a War in Academic Publishing.” Mr. Jacobs is no neutral participant.

What happens when angels and demons battle in heaven? Islam, Judaism, and Christianity all have a story of cosmic conflict—some depict all-out war, while others are more courtroom drama.

Milton didn’t make up the fight with Satan, though. “There was war in heaven,” says the Book of Revelation.