Isaiah 58:6-12 – The Fast that God Chooses
SummaryProper fasting is not mere refraining from food, but a commitment to justice and the poor. This is where God's people will find life.
Isaiah 58 shares the condemnation of hypocritical worship practices found so often in the prophets (for example, Isaiah 1:12-17; Amos 5:21-24; Micah 6:6-8). Jesus, too, was critical of fasting for external reward (Matthew 6:16-18). Proper fasting, says Isaiah, is to loose the bonds of injustice, let the oppressed go free, feed the poor, and clothe the naked. All of this is just what God announced as the mission of Cyrus and the servant in Second Isaiah (42:6-7), and it will be the commission to the speaker of Isaiah 61:1-3. In other words, fasting is not simply a ritual exercise done by an individual for his or her own benefit; by freeing the worshiper from concern for the self, fasting partakes of God's mission of justice and liberation for all people, thus making new both giver and recipient.
The Hebrew text of vv. 10-11 makes clear how this works in its repeated use of the word for "soul" or "self" (Hebrew nefesh): "If you offer your nefesh [your self, your soul] to the hungry and satisfy the nefesh of the afflicted.…The LORD will…satisfy your nefesh in parched places…." In other words, as you pour yourself out for others, you will find yourself--or, as Jesus said, "Those who find their life will lose it, and those who lose their life for my sake will find it" (Matthew 10:39).
The text includes another amazing promise: "You shall cry for help, and [God] will say, Here I am" (v. 9). "Here I am" is the typical and appropriate biblical response of a person called by a superior or by God. In this book, it was Isaiah's response when God commissioned him to be a prophet (see the discussion of Isaiah 6, above). But now, surprisingly, God takes those words of quintessential human response into God's own mouth. Now, God says, "Here I am"--saying, as it were, "I am at your disposal." This happens three times in the latter part of Isaiah (here; 52:6; 65:1), demonstrating the remarkable inclination toward incarnation of God, as portrayed in this material.