Forecasting future events by the Bible. The plan was to open the sacred volume at random, and lay your finger on a passage without looking at it. The text thus pointed out was supposed to be applicable to the person who pointed it out. (Greek, biblia, Bible; manteia, prophecy.) (See Sortes.)
Another process was to weigh a person suspected of magic against a Bible. If the Bible bore down the other scale, the accused was acquitted.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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