In the days of those kings, the God of heaven will set up a kingdom that will never be destroyed, nor will it be left to another people. It will shatter all these kingdoms and bring them to an end, but will itself stand forever.
The Jews agree with us in thinking this passage cannot be otherwise understood than of the perpetual reign of Christ, and willingly and eagerly ascribe to the glory of their own nation whatever is written everywhere throughout the Scriptures; nay, they often cry down many testimonies of Scripture for the purpose of boasting in their own privileges.
Daniel here gives full satisfaction to Nebuchadnezzar concerning his dream and the interpretation of it. That great prince had been kind to this poor prophet in his maintenance and education; he had been brought up at the king's cost, preferred at court, and the land of his captivity had hereby been made much easier to him than to others of his brethren.
Commenting on Daniel 2:31-45
And in the days of these kings, &c. Not of the Babylonian, Persian, and Grecian kings; nor, indeed, of the old Roman kings, or emperors; but in the days of these ten kings, or kingdoms, into which the Roman empire is divided, signified by the ten toes, of different power and strength.