'Sackcloth' in the Bible

"And it will come about that instead of fragrance there will be a stench; instead of a belt, a rope; instead of well-set hair, baldness; instead of a fine robe, sackcloth; and instead of beauty, shame.

In its streets they wear sackcloth; on its rooftops and in its squares everyone wails and falls down weeping.

at that time the LORD spoke through Amoz's son Isaiah: "Go loosen the sackcloth that's around your waist, and take your sandals off your feet." So that's what he did: he went around naked and barefoot.

On that day the Lord GOD of the Heavenly Armies called for weeping and mourning, for shaving heads and wearing sackcloth.

So tremble, you ladies of leisure! Shudder, you daughters who feel so complacent! Strip down and make yourselves naked down to the waist! Then wrap yourself in sackcloth and beat your breasts.

As soon as Hezekiah the king heard this, he tore his clothes, dressed himself in sackcloth, and went into the LORD's Temple.

Then he sent Eliakim, who was in charge of the palace, Shebna the secretary, and the senior priests, all wearing sackcloth, to Amoz's son, the prophet Isaiah.

I clothe the skies with darkness and make sackcloth their covering."

"Is this the kind of fast that I have chosen, merely a day for a person to humble himself? Is it merely for bowing down one's head like a bulrush, for lying on sackcloth and ashes? Is this what you call a fast, an acceptable day to the LORD?