he will turn back
The act of turning back implies repentance and a return to a previous state of faithfulness. John the Baptist's ministry was characterized by a call to repentance, as seen in Matthew 3:1-2. This turning back is not just a physical return but a spiritual renewal, aligning with the prophetic tradition of calling Israel to return to God, as seen in Malachi 4:5-6, which speaks of Elijah's return to turn the hearts of the people.

to the Lord their God
This phrase emphasizes the covenant relationship between Israel and Yahweh, their God. The use of "Lord" underscores God's sovereignty and authority, while "their God" highlights the personal and communal relationship. The call to return to the Lord is a central theme in the prophetic literature, such as in Hosea 6:1 and Joel 2:12-13, where the people are urged to return to God with all their hearts. This turning back is a preparation for the coming of Jesus Christ, who fulfills the role of the Messiah and establishes a new covenant.

- The angel told Zechariah, “Many of the sons of Israel he will turn back to the Lord their God” (Luke 1:16). That opening word—“Many”—reminds us of a wide but not universal impact.

- John’s ministry would reach large crowds, just as Matthew 3:5–6 records: “People went out to him from Jerusalem and all Judea and the whole region around the Jordan.”

- God’s grace is abundant, yet personal choice remains. Acts 2:41 shows a similar scene after Peter’s sermon: “About three thousand souls were added.” The Lord works on a grand scale, but individuals still respond one by one.

- The focus is the covenant people, descended from Abraham. Exodus 19:5–6 calls Israel “a kingdom of priests and a holy nation.”

- By John’s day, many Israelites had drifted into ritual without relationship (see Matthew 15:8–9).

- Romans 9:4–5 reminds us of Israel’s privileges—“the covenants, the giving of the Law, the temple service, and the promises.” John’s mission was to stir these very sons and daughters to embrace those blessings afresh.

- “He” is John the Baptist, promised in Luke 1:13–17 and foretold in Malachi 4:5–6.

- Turning back speaks of repentance—changing direction. Luke 3:3 summarizes John’s message: “He went into all the region around the Jordan, preaching a baptism of repentance for the forgiveness of sins.”

- The phrase echoes Isaiah 40:3: “Prepare the way for the LORD.” John’s call was not mere moral reform; it was a decisive pivot from sin toward God, preparing hearts for the Messiah.

- Repentance always involves action. Acts 26:20 records Paul’s similar charge: “that they should repent and turn to God, performing deeds worthy of repentance.”

- The destination matters. John was not gathering followers for himself; he was directing them “to the Lord their God.”

- Deuteronomy 30:2 had long urged Israel, “When you and your children return to the LORD your God…He will restore you.” John’s ministry reawakened that promise.

- Hosea 14:1 pleads, “Return, O Israel, to the LORD your God, for you have stumbled by your iniquity.” John’s preaching revived this prophetic heartbeat.

- Ultimately, the “Lord” to whom John pointed is revealed in Jesus. John 1:29: “Behold, the Lamb of God who takes away the sin of the world!” Repentance finds its fulfillment in faith in Christ.

Luke 1:16 declares that John the Baptist would be God’s instrument to bring a great number of Israelites back into genuine, covenant-faithful relationship with the Lord. Many—though not all—would respond. His audience was the historic people of God, long privileged yet often wayward. John’s call to “turn back” was a summons to heartfelt repentance, moving from outward religion to inward devotion. And the endpoint of that turning was not John himself but “the Lord their God,” ultimately revealed in Jesus Christ.