Mark 9:38-42

John said unto him, Teacher, we saw one casting out demons in thy name; and we forbade him, because he followed not us. But Jesus said, Forbid him not: for there is no man who shall do a mighty work in my name, and be able quickly to speak evil of me. For he that is not against us is for us. For whosoever shall give you a cup of water to drink, because ye are Christ’s, verily I say unto you, he shall in no wise lose his reward. And whosoever shall cause one of these little ones that believe on me to stumble, it were better for him if a great millstone were hanged about his neck, and he were cast into the sea.