"I shall sing to the Lord," who is a Judge. After celebrating God as powerful, rich, wise, and merciful, the Mekhilta arrives at the attribute that ties all the others together: justice. The Israelites sang at the sea because they witnessed perfect judgment — the guilty punished, the innocent saved, with no collateral damage and no appeal necessary.
The first proof text comes from Moses' instruction to the judges of Israel: "For the judgment is God's" (Deuteronomy 1:17). Human judges preside over earthly courts, but the judgment itself belongs to God. Every verdict rendered on earth is, in its truest form, a reflection of divine justice operating through human instruments. The judges do not own the justice they dispense — they are borrowing it.
The Psalmist deepens the picture: "God stands in the assembly of the mighty. In the midst of the judges shall He judge" (Psalms 82:1). God is not absent from human courtrooms. He stands among the judges, evaluating their judgments, judging the judges themselves. No verdict escapes divine review. Finally, the Mekhilta cites the verse that became the cornerstone of Jewish theodicy: "The Rock, perfect is His work, for all of His ways are judgment" (Deuteronomy 32:4). God's judgment is not merely frequent or reliable. It is perfect. Every act of God — including the drowning of the Egyptians, including the salvation of Israel — is an expression of flawless justice. The Israelites sang because they had seen it with their own eyes.