9:38 This is the only place where the synoptic writers mentioned John speaking out alone. John spoke for the other disciples in the house (v. 33).
Evidently the exorcist was a believer in Jesus though not one of the Twelve or possibly not even one who spent much time following Jesus around. He evidently commanded demons to leave the people they afflicted by using Jesus' name. The Twelve apparently did not mind that this man claimed Jesus' authority to exorcize demons. They objected to his actions because Jesus had not commissioned him to do so as He had the Twelve (3:14-15). Perhaps his success and the recent failure of the nine disciples irritated them further. In view of what Jesus had just said about receiving little children, John wondered if the Twelve had done right in rebuking the man. They had tried to protect Jesus' honor by rebuking him (cf. Num. 11:26-29).
9:39-40 Jesus did not mind that the man was casting out demons by invoking His name. Since the man had such respect for Jesus he would not speak against Him soon. By casting out demons he showed that he was not against Jesus. Jesus expressed the opposite truth in Matthew 12:30: "He who is not with me is against me."There is no neutral ground regarding one's orientation to Jesus. Jesus' point was that the disciples should not view the exorcist as an antagonist just because he was not part of their group. He was doing God's will and would not oppose them.
9:41 The connecting idea with what precedes is the "name."Not only would the exorcist receive God's blessing, but anyone who does anything to help another person using even the name of a disciple of Jesus would receive His reward. This help extends to the almost insignificant act of giving a cup of cold water to some thirsty person. This act was much less helpful than delivering from demonic affliction.
This is one of the rare occasions when Jesus used the title "Messiah"of Himself. His use of it here makes the lesson even more forceful. The person giving the cup of cold water might have only a superficial understanding of Jesus. Nonetheless if that person offered simple hospitality to one of Jesus' disciples because he was a disciple of "Messiah"that one would receive God's blessing.
9:42 This verse gives the other side of the idea just expressed. Anyone who discouraged a disciple of Jesus from following Him faithfully could expect severe treatment from God. Probably Jesus used the little child present to illustrate a childlike disciple (vv. 36-37; cf. Matt. 18:3-14). Jesus referred to a large donkey-driven millstone (Gr. mylos onikos), not a small one that people turned by hand (Gr. mylos).
"This brief incident stands as a firm rebuke to the spirit of sectarianism. It condemns that exclusive attitude which insists that only those who carry on their work in harmony with our own views and practices can be accepted as really doing God's work. If they demonstrate that they are on God's side in the war with Satan, even though their views may be imperfect, they must not be condemned for such work or regarded with abhorrence."231
John evidently learned this lesson well as evidenced by the frequent references to loving one another that appear in his writings.
