And also the final verse (Exodus 15:19): "For the horses of Pharaoh went with his chariots and his horsemen into the sea, and the Lord brought back the waters of the sea upon them, but the children of Israel walked on dry land in the midst of the sea." This implies that it is also referring to the salvation of Israel, and indeed Ibn Ezra interpreted it this way. However, many early commentators, such as Ramban, Chizkuni, Sforno, and others, explained that this verse is not part of the song, but rather an addition, and our question remains valid.

The verse itself requires explanation: what is it teaching us, since on its surface it repeats what was already stated earlier? Sforno (there) explained: "And this that we said 'then sang,' was when the horses of Pharaoh went with his chariots and horsemen into the sea, and the Blessed God drowned them while the children of Israel were walking on dry land in the midst of the sea. Before they exited, they began to sing." And still, it requires explanation, what does this teach us?