And John answered him, saying, Teacher, we saw one casting out demons in your name, and he followed not us: and we forbade him, because he followed not us.
All Commentaries on Mark 9:38 Go To Mark 9
Augustine of Hippo
AD 430
His situation was in some ways parallel to that of one who, while not yet embracing the sacraments of Christ, nevertheless esteems the Christian name so far as even to welcome Christians and accommodate oneself to their service for this very reason and no other—that they are Christians. This is the type of person of whom it was said that he would not lose his reward. This does not mean, however, that such individuals ought prematurely to imagine themselves quite safe and secure simply on account of this kindness which they cherish toward Christians, while at the same time remaining uncleansed by Christ’s baptism, and not thereby incorporated into the unity of his body. Such persons are now already being guided by the mercy of God in such a way that they may also come to receive these loftier gifts, and so depart this present world in safety. Such persons assuredly are more profitable servants even before they become a part of the body of Christ, than those who, while already bearing the Christian name and partaking in the sacraments, recommend courses of action which are only fitted to drag others along with them into eternal punishment.