'Ashes' in the Bible

He feedeth on ashes; a deceived heart hath turned him aside, that he cannot deliver his soul, nor say, Is there not a lie in my right hand?

Is such the fast that I have chosen, a day for a man to afflict his soul, that he should bow down his head as a bulrush, and spread sackcloth and ashes under him? Wilt thou call this a fast, and a day acceptable to Jehovah?

to appoint unto them that mourn in Zion, that beauty should be given unto them instead of ashes, the oil of joy instead of mourning, the garment of praise instead of the spirit of heaviness: that they might be called terebinths of righteousness, the planting of Jehovah, that he may be glorified.