mighty to save: God served as Israel’s divine warrior and redeemer (see Psalm 24:8–10; Isaiah 42:13; Habakkuk 3:8–15). One of God’s titles is “the Mighty God” (Isaiah 10:21). This title also refers to the Messiah (Isaiah 9:6).
He will rejoice over you: Jerusalem and all Israel will rejoice in God (Zephaniah 3:14), and God will rejoice over them as a purified and faithful people (see 3:12–13).