Charles Spurgeon Commentary Matthew 9:34

"But the Pharisees said, By the prince of the demons casteth he out demons." — Matthew 9:34 (ASV)

Of course, they had some bitter condemnation ready. Nothing was too harsh for them to say about Jesus. They were hard pressed when they resorted to this statement, which our Lord, in another place, so easily answered. They hinted that such power over demons must have come to Him through an unholy compact with “the prince of the devils.” Surely this was bordering on the unpardonable sin.

But the Pharisees said, He casts out devils through the prince of the devils.

There is always somebody or other who has an ugly word to put in. It does not matter how much God may bless the gospel; there is no stopping the sneers and objections. But the mercy is that it does not matter much. Our Lord was not hurt, and the work went on, despite all the fault-finding of the Pharisees.

But the Pharisees said, He casteth out devils through the prince of the devils.

Of course, they had some bitter remark ready. Nothing was too bad for them to say about Jesus. They were hard pressed when they resorted to this statement, which our Lord answered so easily in another place. They hinted that such power over demons must have come to him through an unholy compact with "the prince of the devils." Surely this was going very near to the unpardonable sin.