“When you pass through the waters, I will be with you; and through the rivers, they shall not overwhelm you.”
God speaks of the waters as a certainty, not a hypothesis. Your flood did not catch Him off guard — He was already in the promise.
The promise is not dry ground; it is company in deep water. God does not shout instructions from the bank — He gets in with you.
The rivers may rise, but they cannot overwhelm you. The waters have a boundary God Himself has set.
The verse goes on: not even the fire will burn you. Waters or flames, the rule holds — trials surround, but they do not consume those who belong to God.
One verse earlier, God gives the why: "I have called you by name; you are mine." The promise in the waters flows from belonging.
Act: name today's deepest water and pray Isaiah 43:2 over it before breakfast: "When I pass through…, You will be with me."