Bring a group of people together for any sustained length of time and there will be trouble. This is what the church is: an assembly of people. The church is not a building. The church is not an event. The church ("ecclesia" in Koine Greek) is an assembly of people. Therefore, to put the opening sentence another way, establish a church and there will be trouble. Why is there fear of commitment? Because we don't do it very well.
As soon as we decided to go our own way and stop following our Father in Heaven, we got lost. As soon as we stopped listening to the instructions of the Creator, we tried to hide from him, we failed to take responsibility for our actions and blame each other, and made life much, much more difficult for ourselves.
That's why Jesus came: in order for us to have life to the full. He came to save us. He came to save us from our sin (our rebellion against God; missing the mark).
And so, Jesus speaks plainly to his disciples about what happens when one of them sins (misses the mark). He doesn't tell a parable. He doesn't give a riddle. He doesn't ask a question that we are to seek the answer to. Why? Because Jesus wants to be clear on this inevitably important circumstance within his church.
Yes, sin is inevitable. We are imperfect creations striving to mature under a perfect Creator. Someone who is a part of a church who sins does not show a church that has failed. It's not the act of sin that disproves the effectiveness of making disciples. A church is failing when it fails to deal with the sin, especially when it fails to deal with the sin in the plain manner that Jesus prescribes.
Whenever someone within God's people is living against God, Jesus tells us to deal with it privately, directly and decisively.
When considering Jesus' instructions, it is important to remember that Jesus is responding to his disciple's question of "Who is the greatest in the kingdom of heaven?" Jesus answers initially with, "Whoever becomes humble like this child is the greatest in the kingdom of heaven."
Whenever we deal with one another, we must be humble. Regarding ourselves as servants of others is the safest place to be. There is no competition. There is no leveling. In humility, we are to regard others more important than ourselves. How do we commit to one another? How do we become a cohesive group of people striving together after Christ? How do we become great? By humbling ourselves and helping our brother and sister to become great.
As brothers and sisters who share the same name, therefore, it should disturb us greatly when we think that a family member is destroying themselves by living contrary to the King. We should hope beyond hope that we are mistaken. We should easily think of a time when we have behaved similarly and were thankful that someone reminded us of who we are supposed to be and what we have turned away from.
Keeping this attitude, we approach the person privately. No need to humiliate or make ourselves look better. We aren't. Besides, we may be completely wrong. It is easier to have an honest conversation privately, isn't it? No need to save face or make a show. It's just me and you. No cameras. No audience. Just us, off the record.
If you find that you were mistaken, there is no embarrassment for you. If he/she finds that he/she is mistaken, there is no embarrassment for them. If they stop, if they turn, you have accomplished what your King wanted you to do. And you continue worshipping Jesus together.
But, if it becomes clear that he/she is still harming the church through their rebellion against the head of the church, then it is still private, but with only one or two others who are witnesses. Jesus is referring to the way prescribed in the Law. One could not simply accuse someone of wrong and expect them to be punished. There needed to be two or more witness to corroborate the breaking of the Law.
Maybe the witnesses will show you your fault. Maybe the witnesses will be an excellent intervention to the one you are trying to convince to change. Either way, the desired outcome of this horrible exercise is the elimination of rebellious living. If that occurs, you continue worshipping Jesus together.
But, if it becomes clear that he/she is still harming the church through their rebellion against the head of the church, then it must be brought before the entire church in a loving manner. If it gets to this point, it will be a mess. One who is standing on their rebellious pride will be incapable of acting with the humility that Christ prescribes.
"...let such a one be to you as a Gentile and a tax collector."
Do these sound like harsh words to you? Think about how Jesus treated Gentiles and tax collectors. He continally preached to them to "Repent. For the Kingdom of Heaven is at hand" It was up to them whether to become a part of the family. As a part of the family, Jesus shared intimate details of the Kingdom. He taught them about how the Spirit moved among them. He demonstrated how they could do what he was doing.
But, for those who insisted on being outside the family, Jesus could only ask them to "Repent. For the Kingdom of Heaven is at hand." Trying to serve with someone who refuses to serve with you is like depending on a toddler to help put out a house fire. You end up spending more energy, time and resources on the toddler instead of putting out the fire you were called to put out in the first place.
Churches do not exist to put on rock concerts, help us feel better, teach our children values, serve us tea and coffee, give us a ritual to check off our religious to-do list, entertain or give us friends and jobs. Churches exist, Jesus gathers people together, for one primary reason: to make disciples of Jesus, full-stop.
Father, please remind me to be humble, serve my brothers and sister in Christ well, and help them to be great. Thank you for including me in your wonderful, powerful family.