Does Luke 9:49, Mark 9:38, & Mark 16:17 Contradict?

Does Mark 9:38, Mark 16:17, & Luke 9:49 Contradict?

According to some, the Bible contradicts over who can do great works:  

In Mark 9:38 & Luke 9:49, we see John rather pompously speaking on how they tried to prevent someone from casting out demons only for Jesus to condemn him in both books saying, "But Jesus said to him, “Do not hinder him; for he who is not against you is for you," (Luke 9:50 NASB1995) and "But Jesus said, “Do not hinder him, for there is no one who will perform a miracle in My name, and be able soon afterward to speak evil of Me. For he who is not against us is for us," (Mark 9:39-40 NASB1995). 

In Mark 16:17, we see believers have the ability to cast out demons and speak in tongues. People will claim these contradict for in Mark 9:38 & Luke 9:49 a nonbeliever brings out a demon but in Mark 16:17 it seems only believers can; however, this is an incorrect reading. In Mark 16:17, Jesus merely states that believers will have these abilities, not that they alone will. This supposed contradiction comes from a mere misreading of the text. The Greek "σημεῖα δὲ τοῖς πιστεύσασιν ταῦτα παρακολουθήσει: ἐν τῷ ὀνόματί μου δαιμόνια ἐκβαλοῦσιν γλώσσαις λαλήσουσιν καιναῖς," (Mark 16:17) gives us no reason to belief an idea of "only" would be there.

Work Cited:

New American Standard Bible®, Copyright © 1995 by The Lockman Foundation. All rights reserved.