Kevin, I appreciate your response. I'll make a couple of comments.
The Matthew 18:15-17, in my opinion, does not have to do with another believer calling me names or mocking me, as Barry has done. Instead, I see it as having to do with settling a more substantial wrong, a trespass. I don't think that Jesus intended for me to drag Barry in front of my church (logistically difficult) every time he makes a joke or sarcastic remark about me. [since step 1 and step 2 have already been tried, and did not work] Besides, most decent people already consider him "a heathen man and a publican".
Second, Matthew 18 and Luke 17:1-5 are not the same incident being repeated in the Gospel. Offense and forgiveness are the topics being discussed in both, but the setting is not quite the same. It is not the same conversation. Jesus, as a perfect teacher would have repeated His messages under varying circumstances.
Yes, there is different information given in Luke, but the context shows that "offenses" is the center of the conversation. The passage in Matthew 18:21-35 was in response to Peter's question, so the focus was on forgiveness (see verse 35).
Boy, are we (I) off-topic!