Being and Becoming a City on a Hill
I. City on a Hill
But, according to Bonhoeffer, in the Sermon on the Mount and especially in the sayings of Jesus, Matthew challenges all attempts to make invisible what it means to follow Jesus: “You are the light of the world. A city built on a hill cannot be hid” (Matt. 5:14). Bonhoeffer observes that any Israelite could not help but be reminded of Jerusalem by an appeal to such a city, only now that city is constituted by a community of disciples. Accordingly,
the followers of Jesus are no longer faced with a decision. The only decision possible for them has already been made. Now they have to be what they are, or they are not following Jesus. The followers are the visible community of faith; their discipleship is a visible act which separates them from the world—or it is not discipleship. And discipleship is as visible as light in the night, as a mountain in the flatland.
To flee into invisibility is to deny the call. Any community of Jesus which wants to be invisible is no longer a community that follows him. (Bonhoeffer 2001, 113)
John Howard Yoder makes the striking observation that after the Constantinian shift the meaning of the word “Christian” changes (1984, 135–49). Prior to Constantine it took exceptional conviction to be a Christian. After Constantine it takes exceptional courage not to be counted as a Christian. The establishment of Christianity had the ironic result of making paganism morally compelling. This change in status of what it meant to be Christian, according to Yoder, called forth a new theological development, “namely the doctrine of the invisibility of the church.” Before Constantine, Christians assumed as a matter of faith that God was governing history even in the person of the emperor, but they knew that God was present in the church. After the Constantinian establishment, Christians knew that God was governing the world in Constantine, but they had to take it on faith that within the nominally Christian mass there was a community of true believers. No longer could being a Christian be identified with church membership, since many “Christians” in the church had not chosen to follow Christ. Now to be a Christian is transmuted to “inwardness” (1984, 136–37).