Two agents are responsible for this work. John the Baptist, as prophet, will go on before the Lord to prepare the way for him. In the context of the hymn, it is best to see the Lord as a reference to God the Father, since he is the source of all the activity the hymn describes (as also in 1:17). Luke 1:76-77 speaks of his way and his people, a reference that looks back to 1:68, where the people are God's. For Luke, God is the producer-planner and Jesus is the plan's directing agent. John's preparation involves giving knowledge of salvation through the forgiveness of their sins. Forgiveness is a major Lukan theme (Lk 24:47; Acts 2:38; 5:31; 10:43; 13:38; 26:18).
Forgiveness is also a principal component of the expression of God's tender mercy. He is the one who makes the dayspring dawn upon us from on high, or in the NIV rendition, the rising sun . . . come to us from heaven. This is a reference to the sun's dawning in the morning. The Davidic horn (v. 69) is an image of light (Num 24:17; Is 11:1-10). The image of light will be important in Acts (13:47; 26:17-20) as well as in Luke (2:32). The picture is of a world cloaked in darkness and death, desperate for someone to lead it into light and life. For Zechariah, this rescue is Messiah's mission. The Christ is the bearer of forgiveness as his day dawns. Once his day dawns, the light of the "Sun" never sets. He is the one who guides our feet into the path of peace. Even the righteous Zechariah recognizes the need to be totally dependent on the one God will send. Those who are righteous know that the only true journey in life is the one taken in the hands of God. In Luke 1, Zechariah has grown from a figure of doubt to an example of dependence.
So John and Jesus come by God's mercy to prepare and lead God's people. John will proclaim salvation, but Jesus will take them to it.
For this reason Luke notes John's growth briefly and ends the chapter by placing John in the desert, where he will minister to the nation. Then Luke turns the story's spotlight from John and his birth and shines it on the star of his narrative, Jesus, the Davidic horn and king who delivers his people into the light.
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