This is a little long, but I think you will find it interesting!!!
The book "ORGANIZED TO ACCOMPLISH OUR MINISTRY" (1989) written by the Watchtower Society has this to say about Matthew 18:15-17 starting on page 142:
"When giving counsel, Jesus outlined some specific procedures for resolving problems of serious wrongdoing, such as fraud or slander, that may arise between fellow Christians........
"If someone in the congregation has committed such a serious sin against you personally, do not be hasty to turn to the overseers, or someone else, requesting them to intervene in your behalf. First of all, as Jesus counsels, speak with the one against whom you have a complaint. Try to resolve the matter between just the two of you without involving anyone else at all. If the matter can be straightened out in this way, the one who has sinned will certainly appreciate the fact that you have not told others about his sin and have not marred his good reputation among others in the congregation. You will have "gained your brother".
"Where the sinner accepts reproof, seeks forgiveness and straightens the matter out, Jesus states there is no need to carry the matter further. This fact shows that, although serious, the offenses here discussed were limited in nature to such as could be settled between the individuals involved. This would NOT include such offenses as FORNICATION, ADULTERY, HOMOSEXUALITY, BLASPHEMY, APOSTASY, IDOLATRY AND SIMLAR GROSS SINS that should be reported to the elders and handled by them. When the Law covenant was in force, these sins required more than forgiveness from an offended individual.
"In view of this and in view of the illustration that Jesus subsequently gave, as recorded at Matthew 18:23-35, the sins considered in Matthew 18:15-17 evidently were sins such as those involving financial or property matters-failure to make proper payment for something or some action involving a measure of fraud......
"If the one who sinned against you cannot be convinced by your reasoning with him alone, then do as Jesus said and take one or two others along and speak with him again. The one or two you take with you should have the same objective, that of gaining your brother. Preferably they should be witnesses of the alleged wrongdoing, BUT IF THERE ARE NO EYEWITNESSES, YOU MAY CHOOSE TO TAKE ALONG RESPONSIBLE BROTHERS WHO BECOME WITNESSES TO THE EVIDENCE PRESENTED IN THE DISCUSSION.......
"But if you are convinced that your brother has sinned against you and it has not been resolved either when you spoke with him alone or when you went to him with one or two others, and if a serious sin is involved so that it would be wrong just to let it pass, then you should report the matter to the overseers of the congregation.......
"If upon investigation it should become evident to the shepherds of the flock that the brother has indeed committed a serious sin against you and yet has been unwilling to repent and make appropriate amends, it may become necessary for the overseers to EXPEL THE UNREPENTANT WRONGDOER and in that way protect the flock and safeguard the cleanness of the congregation." (caps mine)
The Watchtower has cited Matthew 18:15-17 as supporting in "principle" their two eyewitness rule requirement. Yet, their own congregation manual does NOT require the witnesses to be eyewitnesses, they can just as well be witnesses to the presentation of evidence that a sin was committed!
In addition, the elders can move to disfellowship someone just on the basis of the evidence provided though there were NO EYEWITNESSES!
HOW IS IT THEN THAT A BROTHER CAN BE DISFELLOWSHIPPED FOR FRAUD THOUGH THERE WERE NO EYEWITNESSES, YET ANOTHER BROTHER CAN ESCAPE DISFELLOWSHIPPING BECAUSE THERE WAS NO EYEWITNESS TO HIS RAPE OF A CHILD???!!!
IW