Charles Ellicott Commentary Matthew 11:18

"For John came neither eating nor drinking, and they say, He hath a demon." — Matthew 11:18 (ASV)

He hath a devil — The phrase was a common one, simultaneously asserting the fact of insanity and ascribing it to demonic possession as its cause (John 8:48). This was the explanation the scribes gave for John’s austerities. To them, the locusts and wild honey were the diet of a madman.