Question: "What is the zeal of the Lord, and what assurance does it give us (Isaiah 9:7)?"
Answer: In Isaiah 9:1–7, the prophet Isaiah saw dark days on Israel’s horizon. But with prophetic vision, he pierced through the oncoming hardship, punishment, and oppression to a time of glorious deliverance and abundant hope. This hope would dawn in the form of a newborn child, Israel’s promised Messiah: “For to us a child is born, to us a son is given, and the government will be on his shoulders. And he will be called Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace. Of the greatness of his government and peace there will be no end. He will reign . . . with justice and righteousness from that time on and forever. The zeal of the Lord Almighty will accomplish this” (verses 6–7).
The zeal of the Lord is closely related in meaning to the jealousy of God. In the ancient Near East, pagan peoples used zeal to describe the jealous tension between rival gods. Israel applied the expression to define the Lord’s intense love, protective dedication, and everlasting loyalty toward His own people and to His divine purposes for them. Isaiah said that the zeal of the Lord would cause everything that he had foreseen in Israel’s future to happen. In other words, Isaiah hung all his prophetic hope on the passionate commitment of Israel’s God toward His people.
The zeal of the Lord is God’s divine jealousy with which He operates to protect and restore His people: “For out of Jerusalem will come a remnant, and out of Mount Zion a band of survivors. The zeal of the Lord Almighty will accomplish this” (Isaiah 37:32; see also 2 Kings 19:3; Zechariah 1:14; 8:2). This zeal is the foundation for God’s demand for exclusive loyalty, as expressed in the Ten Commandments. God prohibits His worshippers from bowing down to any other gods (Exodus 20:3–5; see also Exodus 34:14; Deuteronomy 5:9). He alone is our God. In His jealous zeal for us, God cannot conceive of His beloved children offering their affection or allegiance to any other: “For the Lord your God is a consuming fire, a jealous God” (Deuteronomy 4:24; see also Joshua 24:19).
The zeal of the Lord seeks a response of faithfulness and obedience from His people. It does not accept disloyalty. When Israel turned from Yahweh to serve foreign gods, the Lord became jealous for His own reputation (Deuteronomy 32:16, 21; Isaiah 42:8). If we are unfaithful to the Lord, His zeal will cause Him to act in judgment (Deuteronomy 6:15).
When Nahum announced God’s judgment upon Nineveh because of its great wickedness, cruelty, and idolatry, the prophet began, “The Lord is a jealous and avenging God” (Nahum 1:2). In the original language, the adjective translated “jealous” here means “zealous, fiercely protective, and unaccepting of disloyalty.” The Bible uses this adjective exclusively to describe God. In fact, Scripture declares that God’s very name is “Jealous” (Exodus 34:14). His jealousy is not like the human emotion of jealousy but rather a “godly jealousy” (2 Corinthians 11:2). As our Creator and Redeemer, God is intensely focused on caring for and protecting us and, when necessary, avenging Himself on the enemies of His people.
The zeal of the Lord assures us of God’s intense love, unstoppable devotion, and relentless commitment to accomplish His purpose in our lives (Isaiah 46:10; 55:10–11; Psalm 138:8; Philippians 2:13). The Lord is our champion who cannot be stopped but will triumph over our every enemy (Isaiah 42:13). Our future and salvation are secure in Him (Jeremiah 29:11; Psalm 62:6–7).