A common misinterpretation is to dismiss all fasting as futile or unnecessary based on this critique of ritualistic practices, ignoring that God desires authentic fasting coupled with ethical actions like loosing chains of injustice and caring for the needy; another error is viewing the passage as solely anti-ritual without recognizing its call for integrated worship that combines inner transformation with outward obedience in the full chapter's context.
Isaiah 58:5
King James Version (1769)
5 Is it such a fast that I have chosen? a day for a man to afflict his soul? is it to bow down his head as a bulrush, and to spread sackcloth and ashes under him? wilt thou call this a fast, and an acceptable day to the Lord?
God, through Isaiah, rejects superficial fasting rituals—such as afflicting the soul merely by bowing the head like a bulrush or spreading sackcloth and ashes—as unacceptable if they lack genuine humility, justice, and compassion; true fasting must involve heartfelt repentance, freeing the oppressed, feeding the hungry, and living righteously, making it a day pleasing to the Lord.