'Sackcloth' in the Bible

Now when Mordecai learned of everything that had been done, he tore his clothes [in mourning], and put on sackcloth and ashes, and went out into the center of the city and cried out loudly and bitterly.

He went [only] as far as the king’s gate, because no one was to enter the king’s gate dressed in sackcloth.

In each and every province that the decree and law of the king reached, there was great mourning among the Jews, with fasting, weeping and wailing; and many lay on sackcloth and ashes.

When Esther’s maids and her eunuchs came and told her [what had happened], the queen was seized by great fear. She sent garments to clothe Mordecai so that he would remove his sackcloth, but he did not accept them.