I make a decree - Compare Daniel 3:29.
That in every dominion of my kingdom - Every department or province. The entire kingdom or empire was made up of several kingdoms, as Media, Persia, Babylonia, etc. The meaning is, that he wished the God of Daniel to be honored and reverenced throughout the whole empire.
Men tremble and fear before the God of Daniel - That they honor and reverence him as God. There is no certain evidence that he meant that he should be honored as the only God; but the probability is, that he meant that he should be recognized as a God of great power and glory, and as worthy of universal reverence. How far this pagan monarch might still regard the other deities worshipped in the empire as gods, or how far his own heart might be disposed to honor the God of Daniel, there are no means of ascertaining. It was much, however, that so great a monarch should be led to make a proclamation acknowledging the God of Daniel as having a real existence, and as entitled to universal reverence.
For he is the living God - An appellation often given to God in the Scriptures, and probably learned by Darius from Daniel. It is not, however, absolutely certain that Darius would attach all the ideas to these phrases which Daniel did, or which we would. The attributes here ascribed to God are correct, and the views expressed are far beyond any that prevailed among the pagan; but still it would not be proper to suppose that Darius certainly had all the views of God which these words would convey to us now.
And stedfast for ever - That is, he is always the same. He ever lives; he has power overall; his kingdom is on an immovable foundation. He is not, in his government, to cease to exist, and to be succeeded by another who shall occupy his throne.
And his kingdom what shall not be destroyed ... - See the Daniel 4:3, note ; Daniel 4:34, note. The similarity between the language used here, and that employed by Nebuchadnezzar, shows that it was probably derived from the same source. It is to be presumed that both monarchs expressed the views which they had learned from Daniel.