Is such the fast that I choose, a day for a person to humble himself? Is it to bow down his head like a reed, and to spread sackcloth and ashes under him? Will you call this a fast, and a day acceptable to the LORD? Is not this the fast that I choose: to loose the bonds of wickedness, to undo the straps of the yoke, to let the oppressed go free, and to break every yoke? (Isaiah 57:5-6)