John Gill Commentary Luke 11:15

"But some of them said, By Beelzebub the prince of the demons casteth he out demons." — Luke 11:15 (ASV)

But some of them said The Pharisees, (Matthew 9:34) (Matthew 12:24) who could not bear that he should be thought to be the Messiah, and therefore put an ill construction on the miracle:

he casteth out devils through Beelzebub, the chief of devils ; in several copies he is called Beelzebul, and in the Arabic and Ethiopic versions; which last adds these words, "and he answered and said, how can Satan cast out Satan?" (See Gill on Matthew 12:20).