“Now in those days John the Baptist came, preaching in the wilderness of Judea, saying, ‘Repent, for the kingdom of heaven is at hand.'” — Matthew 3:1-2.
John [the Baptist] was not offering a better way to live, though a beter way to live was entailed by the kingdom that he proclaimed was near. But it is the proclamation of the “kingdom of heaven” that creates the urgency of John’s ministry. Such a kingdom does not come through our tryin gto be better people. Rather, the knigdom comes, making imperative our repentance. John’s call for Israel to repent is not a prophetic call for those who repent to change the world, but rather he calls for repentance because the world is being and will be changed by the one whom John knows is to come. To live differently, moreover, means that the status quo can be challenged because now a people are the difference.
Stanley Hauerwas, Commentary on Matthew, Ch. 3.