What Does Exodus 15:10 Mean?

"You blew with your wind; the sea covered them; they sank like lead in the great waters." The sea closing is the song's central reversal: "you blew with your wind" (Hebrew: nashafta beruachecha, you blew with your spirit/breath): the same wind/breath (ruach) that opened the sea (verse 8, blast of nostrils) now closes it. The closing breath is the answering act: YHWH's breath opened the sea; YHWH's breath closed it. The sea crossing has the structure of divine breathing: inhale (waters pile up), exhale (waters return). Both acts are one continuous divine breath-action on the sea.

"They sank like lead in the great waters": the lead-sinking simile intensifies the stone-sinking of verse 5: lead is the heaviest common metal, the most reliably sinking material in ancient experience. If a stone sinks to the bottom and stays, lead sinks faster and stays more certainly. The two sinking similes (stone in verse 5, lead in verse 10) form a progression: the enemy sank with the certainty of stone, the speed of lead. Both similes emphasize the irreversibility of Egypt's defeat: sunk objects do not rise; drowned armies do not reconstitute.

The "great waters" (mayim adirim, powerful/majestic waters) of verse 10 picks up the "majestic power" (addir ba'koach) of verse 6's right hand: the same word adir (majestic/great) is applied to YHWH's power and to the waters that express his power. YHWH's majestic right-hand power and the great waters that drown Egypt are both expressions of the same divine majesty. The sea is not an independent force that happens to serve YHWH; it is the specific instrument through which YHWH's majestic power is expressed at this moment of divine-warrior action.