"Jesus said, 'Do not stop him, for no one who does a mighty work in my name will be able soon afterward to speak evil of me. For the one who is not against us is for us' " (vv. 39–40).
Arguments over who was the greatest, in which the disciples engaged on their way to Jerusalem (Mark 9:33–34), demonstrate that the disciples were focused on exclusivity in an unhealthy way during Jesus' earthly ministry. Each of them wanted to be in the select category called "greatest," which by definition excludes everyone except its one member. Each disciple wanted, in essence, to put a wall around himself with a sign that said, "Herein Stands the Greatest; No One Else Allowed."
This exclusionary attitude on the individual level operated also on a larger group level, as indicated in today's passage. Mark 9:38 records the Apostle John's complaint that some people outside the band of disciples who constantly followed Jesus were performing exorcisms in Jesus' name. Immediately, John's protest showed that something was wrong with his understanding. The complaint was that the man "was not following us," not that he "was not following You, Jesus." John had a misplaced sense of priorities; his concern was that the man doing the exorcisms was not part of their little group, and he seemed to have cared little about the man's actual relationship to Jesus.
In responding to John, Jesus said it was wrong for the disciples to try to stop the man, for his works showed that he was on the side of Jesus even if he was not one of the Twelve (vv. 39–40). Essentially, Jesus called John and the others to evaluate the man's relationship to Christ not on the basis of the group to which he belonged but on the basis of the fruit of his ministry. The man was bearing good fruit, so he should not have been treated as being outside the kingdom.
This account demonstrates the error we make when we draw our boundaries in such a limited way that we exclude from God's kingdom anyone who is not part of the particular group to which we belong. Christ's kingdom is larger than one church or one denomination. Of course, this does not mean absolutely everyone who professes to follow Jesus is in fact one of His sheep. There are boundaries to be drawn; for example, Scripture tells us that those who do such things as deny the deity of Christ (John 8:24), add our works to our justification (Gal. 1:6–9; 5:4), or advocate living in ways contrary to God's commandments (2 Peter 2) are not true Christians. But we must be careful to draw boundaries only on essential matters and be willing to work with those who truly belong to Christ even if they are not part of our particular group or congregation.
Coram Deo
Expositing Mark 9:38–41, Dr. R.C. Sproul cautions us in his commentary _[Mark](http://www.ligonier.org/store/mark-hardcover/)_ to avoid the error of thinking all differences between Christians divide us in an essential way as well as the error of thinking that no division is important. We must work with other Christians without compromising the essential truths of the faith. Doing this takes great discernment, and we should be continually asking God to make us a discerning people.
