War of the Meal-sacks
After the battle of Beder, Abu Sofian summoned two hundred fleet horsemen, each with a sack of meal at his saddle-bow (the scanty provision of an Arab for a foray), and sallied forth to Medina. Mahomet went forth at the head of a superior force to meet him, and Abu Sofian with his horsemen, throwing off their mealsacks, fled with precipitation.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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