Zechariah says John will be called a prophet of the Most High and will go before the Lord to prepare his ways. John’s mission includes giving knowledge of salvation to God’s people in the forgiveness of their sins. He also speaks of guiding feet into the way of peace (Luke 1:76–79).
In Luke 1:67–80 Zechariah, newly able to speak, blesses Israel’s God for acting on behalf of his people. He interprets current events as God keeping long-promised commitments to David, the prophets, and Abraham. He describes deliverance from enemies so God’s people can serve without fear. This speech comes in Luke’s opening birth narratives, where angelic announcements and songs interpret the births of John and Jesus before their ministries begin. Just before this, John is born and named, and Zechariah’s speech returns after a long silence.
Zechariah’s speech presents the births of John and Jesus as God acting decisively for “his people.” The text explicitly connects present events to older promises: David’s line, the prophets “from of old,” and God’s covenant oath to Abraham.
A careful answer keeps the immediate passage, the book's argument, and the whole-Bible storyline together, so the question is answered in context instead of as a detached idea.
Start with Luke 1:76-79, then read the surrounding section so the answer stays connected to the passage's flow.
76And you, child, will be called a prophet of the Most High, For you will go before the face of the Lord to make ready his ways,
77To give knowledge of salvation to his people by the remission of their sins,
78Because of the tender mercy of our God, Whereby the dawn from on high will visit us,
79To shine on those who sit in darkness and the shadow of death; To guide our feet into the way of peace."