John Trapp on Matthew 9:4

Verse 4. Wherefore thinke ye evil, &c.] Christ confutes their calumny, and proves himself to be God, and to have power to pardon sin, by discerning and condemning their evil thoughts. I the Lord search the heart, Jer. 17. Satan may give a shrewd guesse:Bart. l. 1 de ver. oblig. and so may men too: as Bartolus writes of Doctour Gabriel Nele, that by the only motion of the lips, without any utterance, he understood all men, perceived and read in every mans countenance, what he meant, &c. But none can certainly know the thoughts of man, but God alone. It is his royalty to know what is in man, Joh. 2. 25.