Crack of Doom

The Crack of Doom is an old term used for the Christian Day of Judgement, referring in particular to the blast of trumpets signalling the end of the world in Chapter 8 of the Book of Revelation. A "crack" had the sense of any loud noise, preserved in the phrase "crack of thunder", and Doom was a term for the Last Judgement, as Doomsday still is.

The phrase is famously used in the Day of Judgement sense by William Shakespeare in Macbeth, where on the heath the Three Witches show Macbeth the line of kings that will issue from Banquo:

(Act 4, scene 1, 112–117)- meaning that Banquo's line will endure until the Judgement Day, flattery for King James I, who claimed descent from Banquo.

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