sackcloth and ashes
Mourning or penitence, as in What I did to Julie's child was terrible, and I've been in sackcloth and ashes ever since. This term refers to the ancient Hebrew custom of indicating humility before God by wearing a coarse cloth, normally used to make sacks, and dusting oneself with ashes. In English it appeared in William Tyndale's 1526 biblical translations (Matthew 11:21), "They [the cities Tyre and Sidon] had repented long ago in sackcloth and ashes."
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