The purpose of this essay is to broaden the way in which the exegetical necessity of trinitarian theology has frequently been understood in the post-Enlightenment period by offering an exegetical-theological interpretation of the birth–infancy narrative in the Gospel of Luke and exploring the implications for exegesis in the opening scene in the body of the gospel. The question of the identify of God is pursued by paying close attention to the movement of the Lukan narrative itself and the influence and presence of the OT within the narrative. The essay, as a form of ecclesial biblical theology, attempts to take seriously the dogmatic tradition of the church primarily from the side of exegesis and, hence, focuses on one aspect of continuity between the bible and the later formulations as generated by the dynamics of a particular biblical text.