from
The Collaborative International Dictionary of English v.0.48
Sackcloth \Sack"cloth`\ (?; 115), n.
Linen or cotton cloth such as sacks are made of; coarse
cloth; anciently, a cloth or garment worn in mourning,
distress, mortification, or penitence.
[1913 Webster]
Gird you with sackcloth, and mourn before Abner. --2
Sam. iii. 31.
[1913 Webster]
Thus with sackcloth I invest my woe. --Sandys.
[1913 Webster]
from
Easton's 1897 Bible Dictionary
Sackcloth
cloth made of black goats' hair, coarse, rough, and thick, used
for sacks, and also worn by mourners (Gen. 37:34; 42:25; 2 Sam.
3:31; Esther 4:1, 2; Ps. 30:11, etc.), and as a sign of
repentance (Matt. 11:21). It was put upon animals by the people
of Nineveh (Jonah 3:8).