You should always fear a coward, because he strikes from behind while you are expecting him in front.
 George Sand, Mauprat (1837). copy citation

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Author George Sand
Source Mauprat
Topic fear
Date 1837
Language English
Reference
Note Translated by John Oliver Hobbes
Weblink https://en.wikisource.org/wiki/Mauprat_(Heinemann)

Context

“All this is a mere sharper's trick. In the old days I have heard him making plans which prevent me from being astonished at his impudence now; so I have but little fear of him." "There you are wrong," replied the abbé. "You should always fear a coward, because he strikes from behind while you are expecting him in front. If John Mauprat were not a Trappist, if the papers he showed me were lies, the prior of the Carmelites is too shrewd and cautious to have let himself be deceived. Never would he have espoused the cause of a layman, and never would he mistake a layman for one of his own cloth.” source