Note 10 at Mk. 9:38: Mark records this instance of one casting out devils between his illustration of the little child and his statement about offending one of these little ones, while Matthew omits it. Mark's inclusion of this instance in the context gives Jesus' statement about offending one of these "little ones" a broader application (see note 2 at Mt. 18:6, p. 216). It no doubt included the little child He had used when making His point, but it also was a warning against coming out against any brother in the Lord because he isn't doing things our way (such as this man who was casting out devils in Jesus' name but was not following them).

There is a place for discipline in the Body of Christ (see note 5 at Mt. 18:17, p. 218; see note 6 at Mt. 18:18, p. 219), but we must be sure that we are enforcing the Word of God and not our own convictions. The scripture didn't say this man wasn't following Jesus. The disciples said that he wasn't following them (this verse), or following with them, as Luke records (Lk. 9:49). This man wasn't following Jesus as His twelve disciples were. He wasn't physically traveling with them, but he was following Jesus' teachings and examples. He was doing the works of Jesus (Jn. 14:12).

We must be careful to never haggle over methods. There are different ways of administrating and operating in the same gift (1 Cor. 12:5-6). Any judging or disciplining must be administered by the direction of the Holy Spirit and not by our own imperfect standards (see note 46 at Mt. 7:1, p. 83).