Our biblical authors deliberately choose their words. Before the rise of redaction criticism 50 years ago, translators weren't always too scrupulous in rendering identical terms used in two different passages by the same author in the same way. For instance, though John employs the same Greek word in Jesus' chapter 2 statement, "My hour has not yet come," as he uses in his chapter 19 observation, "From that hour the disciple took her into his home," old time translators often rendered the latter, "From that time," or "From that moment." No translator today would dare make such a mistake. Specific words and terms convey each biblical author's unique theology. Today they're translated in such a way as to show that uniqueness. The same words are translated the same way, no matter in what part of the work they're found.
That's why it's important to know the exact title Matthew employs for those whom Jesus addresses in today's gospel pericope. Some church documents falsely refer to them as "apostles." Yet the first verse of chapter 18 tells us that it was Jesus' "disciples" who approached him on that occasion and his "disciples" to whom he directs his teaching.
There's a huge biblical difference between disciple and apostle. The former is what all authors of the Christian Scriptures label anyone who follows Jesus, either Jew or Gentile, slave or free, man or woman. In Greek, the word simply means a "go behinder." (It now makes sense why last week Jesus told Peter, "Get behind me Satan!" Disciples are never to get in front of the person they're supposed to be following.")
An apostle, on the other hand, is a disciple who's been sent out on a special mission, as Jesus sent out the Twelve back in chapter 10, or John's Jesus sends out Mary Magdalene in chapter 20. (For practical purposes, this means all apostles are disciples, but not all disciples are apostles.) Though the actual biblical distinction is clear, problems arise toward the end of the second century when some church authorities start to imitate the hierarchical structure of the Roman Empire, and begin to equate apostle with bishop.
Thankfully, there's no such confusion in today's narrative. What Jesus says, he says to all Christians, not just to those in the hierarchy. All disciples are to accept responsibility for one another's behavior, even to the point of confrontational interventions. (Of course, when Jesus tells us to treat someone as "a Gentile or tax collector," we can't forget how his loving treatment of such people created problems for the "good folk.")
As the bishops of Vatican II stressed, our call to follow Jesus and the responsibilities which flow from it aren't brokered through the church's authority structure. All are the people of God; all are to engage in determining God's will for the community. Listen, perhaps for the first time, to Jesus' powerful statement, "Where two or three (disciples) are gathered together in my name, there am I in the midst of them."
Matthew's Jesus presumes all Christians now assume Ezekiel's role as "watchman" for God's people. All are responsible for the community's behavior.
Paul understands that Jesus didn't set up a specific, God-mandated structure to carry on his ministry. He simply implanted a frame of mind in his disciples which would guarantee his words and actions would continue long after his earthly ministry was finished. "Owe nothing to anyone, except to love one another," the Apostle writes, "for the one who loves another has fulfilled the law. . . . Love does no evil to the neighbor; hence, love is the fulfillment of the law."
We, as church, have spent far too much time and effort developing and defending the limits and extent of the rights of those in authority, instead of, as Jesus commanded his disciples, exploring how to do the right thing.