Confession retells rebellion and persistent mercy: Confession and rescue at the sea

We have sinned with our fathers is the doorway, not they have sinned

We have sinned with our fathers, we have committed iniquity, we have done wickedly. Our fathers understood not thy wonders in Egypt; they remembered not the multitude of thy mercies; but provoked him at the sea, even at the Red sea.

The first person plural joins present singers to ancestral failure. Wonders not understood and mercies not remembered sit at the sea itself. This is Israel's confession of Israel's story. It is not a license for later readers to caricature Jews as uniquely faithless, and it is not a Christian morality play about a discarded people.

Nevertheless he saved them, and belief sang after the water covered the enemy

Nevertheless he saved them for his name's sake, that he might make his mighty power to be known. He rebuked the Red sea also, and it was dried up: so he led them through the depths, as through the wilderness. And he saved them from the hand of him that hated them, and redeemed them from the hand of the enemy. And the waters covered their enemies: there was not one of them left. Then believed they his words; they sang his praise.

Name's sake and known power explain the rescue, not the singers' quality. Belief and song arrive after the crossing. The psalm will immediately say they forgot. Mercy here is persistent. Enemy waters are the sea event, not a picture to lay over a modern population.