Matthew 12:28 - Coke's Commentary on the Holy Bible

Then the kingdom of God is come unto you— That is, "You may thereby discover that I am the Messiah, or that king who was promised to the Jews." The miracles of our Lord, and the manner in which he performed them, were manifest demonstrations of his having been sent from God (see John 3:2.), and consequently that what he said of himself was true. But the casting out of devils, in particular, was a miracle which proved Christ to be the Messiah; since he came into the world on purpose to destroy the works of the devils. See 1 John 3:8. John 12:31. Hebrews 2:14 and Beausobre and Lenfant.