In Mark chapter 9, the apostles encounter an alarming scene—they find someone casting out demons in the name of Jesus without official authorization. After a stop-work meeting, they decide that the scab exorcist is acting outside the provisions of the award and should desist immediately or face a campaign of rolling stoppages.
_Jesus, of course, rebukes them for their narrow, sectarian attitude. Jesus is not really talking about false teaching, but about whether it is necessary to wear the right badge and belong to the right club in order to be on the right side. The answer is clearly ‘No’.
_In the New Testament, there is a spectrum of teaching on how we should relate to people with whom we disagree. At one end of the spectrum, there are passages like Mark 9, which warn us not to be too exclusive. We should warmly accept people who labour for the Lord Jesus in different ways or in different places or under different brand names. We should not censure them just because they aren't ‘one of us’.
_At the other end of the spectrum is Galatians 1:6-9—
___I am astonished that you are so quickly deserting the one who called you by the grace of Christ and are turning to a different gospel—which is really no gospel at all. Evidently some people are throwing you into confusion and are trying to pervert the gospel of Christ. But even if we or an angel from heaven should preach a gospel other than the one we preached to you let him be eternally condemned!
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There are a number of other passages that we could place at different points along the spectrum between these two, such as the following:
_With Mark 9 at one end of the spectrum and Galatians 1 at the other, it is not always easy, in the heat of the situation, to work out the right response. It is easy to say in hindsight that Paul was right to oppose Peter and Barnabas over the circumcision issue in Galatians 2. But how would it have been for Paul, eyeball-to-eyeball with Peter, that apostolic heavy weight, and Barnabas, Paul's trusted colleague? In the situation, it is often hard to formulate the right response, especially given our sin and wiles of Satan.
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