Mark 9:39 in the World English Bible
But Jesus said, “Don’t forbid him, for there is no one who will do a mighty work in my name and be able quickly to speak evil of me.
Context
38 And John answered him, saying, Master, we saw one casting out devils in thy name, and he followeth not us: and we forbad him, because he followeth not us.
39 But Jesus said, Forbid him not: for there is no man which shall do a miracle in my name, that can lightly speak evil of me.
40 For he that is not against us is on our part.