One of the Old Testament expressions for sin is "to twist"—to misshape something from its true nature and its intended purpose. That phrasing can sound rather mild, but Psalm 78:57 puts the matter dramatically.
The warrior prepares his weapons for battle, and particularly his bow. He selects the best wood, seasons and shapes it carefully, strings it properly, and puts it in its place, handy for immediate use when needed.
After the Exodus, God calls Israel to take the Promised Land and establish a community there that will serve as a light to the nations. Israel's life with Yhwh will shine as a beacon of righteousness and hope to attract the world to the worship of the world's one true God.
Israel was inspired and encouraged in the most extreme ways possible: seeing God pound the Empire with plagues and death until Egypt finally released Israel from bondage; walking with God through the neatly ordered chaos of the Red Sea; and then witnessing God's final judgment on Israel's enemies. Yet (and "yet" is a key word in this psalm) Israel just won't remain faithful:
Yet they sinned still more against him, rebelling against the Most High in the desert.
Generations later, after God has forgiven Israel and secured them in the Promised Land, they still can't be relied upon to do what God called them to do:
Yet they tested the Most High God, and rebelled against him. They did not observe his decrees, but turned away and were faithless like their ancestors; they twisted like a treacherous bow.
"Like a treacherous bow" leaps off the page.
In a crisis, God reaches for Israel. God could have reached for another bow, another nation, but he has committed himself to Israel as his chosen instrument.
And Israel twists under pressure. Psalm 78:57 literally says that Israel twists and turns—as if to escape God, as if to do all it can to avoid God's service.
God depends upon Israel in the clutch. He has designed and built Israel for just such an occasion. This is the moment of truth.
And instead of remaining strong and true, Israel shows itself to be weak and false, positively treacherous. If Israel had just made clear that it would flounder, let alone rebel, God could have just picked another bow. But Israel purported to be faithful, pretended to be available to God's service.
So Israel proves to be worse than useless. Like Christians who profess the faith, go to church, mouth sacred platitudes, and declare on solemn occasions their heartfelt intention to answer God's call—and who, when the stress comes, twist.
They fire arrows in the wrong directions. Or they fail to fire at all.
Psalm 78 concludes with God setting aside his treacherous failures as rejects (John 15:6 makes clear their destiny) and selecting alternatives who can be relied upon to answer God's call with dependable service, with faithfulness. God is stress-testing his church today and the results are slowly, but inexorably, coming in.
May God help me straighten up in time. You, too.