Contradiction with Matthew 17:20
This verse implies faith as small as a mustard seed can move mountains, contrasting with the disciples' inability to heal due to their lack of faith.
Matthew 17:20: And Jesus said unto them, Because of your unbelief: for verily I say unto you, If ye have faith as a grain of mustard seed, ye shall say unto this mountain, Remove hence to yonder place; and it shall remove; and nothing shall be impossible unto you.
Contradiction with John 14:12
This verse states that believers will do the works that Jesus did and even greater works, which contradicts the disciples' inability to cast out the demon.
John 14:12: Verily, verily, I say unto you, He that believeth on me, the works that I do shall he do also; and greater [works] than these shall he do; because I go unto my Father.
Contradiction with Mark 16:17
This verse promises that those who believe will cast out demons in Jesus' name, contrasting with the disciples' failure to do so in Mark 9:14.
Mark 16:17: And these signs shall follow them that believe; In my name shall they cast out devils; they shall speak with new tongues;
Contradiction with Luke 10:19
This verse gives authority to tread on serpents and scorpions and over all the power of the enemy, which conflicts with the disciples' inability in Mark 9:14.
Luke 10:19: Behold, I give unto you power to tread on serpents and scorpions, and over all the power of the enemy: and nothing shall by any means hurt you.
Contradiction with Acts 1:8
This verse promises believers will receive power when the Holy Spirit comes on them, contrasted with the apparent lack of power in Mark 9:14.
Acts 1:8: But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth. [power...: or, the power of the Holy Ghost coming upon you]
Contradiction with Matthew 10:1
This verse says Jesus gave the disciples authority over unclean spirits, contradicting their inability to drive out one in Mark 9:14.
Matthew 10:1: And when he had called unto [him] his twelve disciples, he gave them power [against] unclean spirits, to cast them out, and to heal all manner of sickness and all manner of disease. [against: or, over]
Contradiction with Luke 9:1
Like Matthew 10:1, this verse states the disciples were given power over demons, conflicting with their failure in Mark 9:14.
Luke 9:1: Then he called his twelve disciples together, and gave them power and authority over all devils, and to cure diseases.