And the scribes and Pharisees began to think, saying: Who is this who speaketh blasphemies? Who can forgive sins, but God alone?

“From the Pharisees themselves therefore the Son of God receives testimony. For it is both more powerful evidence when men confess unwillingly, and a more fatal error when they who deny are left to the consequence of their own assertions. Hence it follows, Who can forgive sins, but God only? Great is the madness of an unbelieving people, who though they have confessed that it is of God alone to forgive sins, believe not God when He forgives sins.”

“(ubi sup.) Now if we suffer bodily, we are enough concerned to get rid of the hurtful thing; but when there has harm happened to the soul, we delay, and so are neither cured of our bodily ailments. Let us then remove the fountain of evil, and the waters of sickness will cease to flow. But from fear of the multitude, the Pharisees durst not openly expose their designs, but only meditated them in their hearts Hence it follows, And they began to reason, saying, Who is this which speaketh blasphemies?”

“And the Scribes and the Pharisees began to reason,.... To think and say within themselves, and it may be to one another, in a private manner: saying, who is this which speaketh blasphemies? what vain boaster, and blaspheming creature is this, who assumes that to himself, which is the prerogative of God? Who can forgive sins but God alone? against whom they are committed, whose law is transgressed, and his will disobeyed, and his justice injured and affronted. Certain it is, that none can forgive sins but God; not any of the angels in heaven, or men on earth; not holy good men, nor ministers of the Gospel; and if Christ had been a mere man, though ever so good a man, even a sinless one, or ever so great a prophet, he could not have forgiven sin; but he is truly and properly God, as his being a discerner of the thoughts of these men, and his healing the paralytic man in the manner he did, are sufficient proofs. The Scribes and Pharisees therefore, though they rightly ascribe forgiveness of sin to God alone, yet grievously sinned, in imputing blasphemy to Christ: they had wrong notions of Christ, concluding him to be but a mere man, against the light and evidence of his works and miracles; and also of his office as a Redeemer, who came to save his people from their sins; and seem to restrain the power of forgiving sin to God the Father, whereas the Son of God, being equal with him, had the same power, and that even on earth, to forgive sin; See Gill on Mar 2:7.”

“Who can forgive sins, but God alone? - If Jesus were not God, he could not forgive sins; and his arrogating this authority would have been blasphemy against God, in the most proper sense of the word. That these scribes and Pharisees might have the fullest proof of his Godhead, he works in their presence three miracles, which from their nature could only be effected by an omniscient and omnipotent Being. The miracles are: 1. The remission of the poor man's sins. 2. The discernment of the secret thoughts of the scribes. 3. The restoration of the paralytic in an instant to perfect soundness. See on Mat 9:5, Mat 9:6 (note).”

“How great is the madness of this unbelieving people, who confessing that God alone can forgive sins, will not believe God when he grants pardon. (St. Ambrose) — They indeed spoke the truth, for none can forgive sins but God only, who forgives our offences by the ministry of others, to whom he has committed this power, both in baptism and penance. But Christ, by forgiving sins as God, i.e. with his own power, clearly proves to all his divinity. (Ven. Bede)”