Mark 9:38-40
[Then] John [the apostle] said to Him, "Teacher, we saw someone driving out evil spirits by using your name, so we told him to stop doing it, because he was not following [You] with us."
Luke 9:49-50
Then [the apostle] John answered and said, "Master, we saw someone driving out evil spirits by [using] your name, so we told him not to, because he was not following [you] with us."
John 3:26
These disciples went to John and said to him, "Rabbi, look, that man who was with you on the east side of the Jordan River [i.e., Jesus], whom you testified about, is immersing people and everyone is going to him." [Note: Actually, it was Jesus' disciples who did the immersing. See 4:2].