Bible Verses About Sackcloth: The Jews lay in, when in deep affliction

Ritzpah the daughter of Ayah took sackcloth, spread it out toward a cliff for herself and stayed there from the beginning of the harvest until water was poured out on the bodies from the sky, not letting the birds land on them during the day or the wild animals at night.

Ach'av, on hearing these words, tore his clothes, put sackcloth on himself and fasted. He slept in the sackcloth and went about dejectedly.

Cohanim, put on sackcloth, and weep! Wail, you who serve at the altar! Come, lie in sackcloth all night long, you who serve my God! For the grain offering and drink offering are withheld from the house of your God.