Contradiction with Matthew 12:24
The Pharisees accuse Jesus of casting out devils by the power of Beelzebub, contradicting the crowd's misunderstanding of Jesus having a devil.
Matthew 12:24: But when the Pharisees heard [it], they said, This [fellow] doth not cast out devils, but by Beelzebub the prince of the devils. [Beelzebub: Gr. Beelzebul]
Contradiction with Luke 23:41
This verse highlights Jesus' innocence, whereas John 7:20 reflects the crowd's false accusation of Jesus having a devil.
Luke 23:41: And we indeed justly; for we receive the due reward of our deeds: but this man hath done nothing amiss.
Contradiction with Mark 3:22
The scribes accuse Jesus of being possessed by Beelzebub, which parallels the unbelief in John 7:20, not a contradiction.
Mark 3:22: And the scribes which came down from Jerusalem said, He hath Beelzebub, and by the prince of the devils casteth he out devils.
Contradiction with John 1:29
John the Baptist testifies Jesus as the sinless Lamb of God, contradicting the accusation of having a devil in John 7:20.
John 1:29: The next day John seeth Jesus coming unto him, and saith, Behold the Lamb of God, which taketh away the sin of the world. [taketh away: or, beareth]