sackcloth and ashes, to be in

sackcloth and ashes, to be in

To be penitent or contrite; in a state of repentance. This term alludes to the ancient Hebrew custom of donning a coarse, dark cloth from which sacks were made and dusting oneself with ashes to signify one’s humility before God. It is mentioned in the Bible: “And I set my face unto the Lord God, to seek by prayer and supplications, with fasting, and sackcloth, and ashes” (Daniel 9:3). The term may be obsolescent.
See also: and, sackcloth
The Dictionary of Clichés by Christine Ammer
See also:
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  • binge-watch
  • cat's paw, (be made) a
  • carrot and the stick, the
  • burned out, to be
  • washboard abs
  • a back number
  • back number
  • be pushing up daisies