Luke 9:49

For John loving much, and therefore much beloved, thinks that they should be excluded from the privilege who did not practise obedience.

But we ought to consider not so much the worker of the miracles, as the grace which was in him, who, by the power of Christ, performed miracles. But what if there should be both those which be numbered together with the Apostles, and those who are crowned with the grace of Christ; there are many diversities in Christ's gifts. But because the Saviour had given the Apostles power to cast out evil spirits, (Matt. 10:8.) they thought no one else but themselves alone was permitted to have this privilege granted to him, and therefore they come to enquire if it were lawful for others also to do this. As if He said, On the side of you who love Christ, are all they who wish to follow those things which conduce to His glory, being crowned with His grace.

Because then our Lord had said, He who is least among you all, the same shall be great, John feared, lest perhaps they had done wrong in hindering a certain man by their own power. For a prohibition does not show the probitor to be inferior, but to be one who thinks himself somewhat superior. Hence it is added, And John answered and said, Master, we saw one casting out devils in thy name, and we forbad him. Not indeed from envy, but to distinguish the working of miracles, for he had not received the power of working miracles with them, nor had the Lord sent him as He did them; nor did he follow Jesus in all things. Hence he adds, because he followeth not with us.