It's in Luke from the start

These first three peace texts in Luke—first the promise of imminent peace to be brought by the Messiah (Luke 1:79); then, immediately, the inauguration of peace in the birth of the Messiah (Luke 2:14); and then, immediately, the confession of Simeon (Luke 2:29–30)—are programmatic for Luke’s Gospel and his entire theological project. They tell us what the ministry of the Messiah consists of: inaugurating the age of peace and thereby creating a community, a people, of shalom—a covenant community that experiences and practices God’s peace and justice.— The Death of the Messiah and the Birth of the New Covenant, page 164