John Calvin Commentary Luke 7:33

"For John the Baptist is come eating no bread nor drinking wine; and ye say, He hath a demon." — Luke 7:33 (ASV)

For John the Baptist came. Leading an austere life, he thundered out repentance and severe reproofs, and sang, as it were, a plaintive song; while the Lord endeavored, by a cheerful and sprightly song, to draw them more gently to the Father. Neither of those methods had any success, and what reason could be assigned except their hardened obstinacy?

This passage also shows us why so wide a difference existed regarding outward life between Christ and the Baptist, though both had the same object in view. Our Lord intended, by this diversity, and by assuming, as it were, a variety of characters, to convict unbelievers more fully; since, while He yielded and accommodated Himself to their manners, He did not bend them to Himself.

But if the men of that age are deprived of every excuse for repelling, with inveterate malice, a twofold invitation which God had given them, we too are held guilty in their persons; for God does not leave untried any sort of pleasing melody, or of plaintive and harsh music, to draw us to Himself, and yet we remain hard as stones.

They called John a demoniac, just as people with unsound minds, or those whose minds are disturbed, are usually called madmen.