Daniel 4:31 (ESV)

31 While the words were still in the king’s mouth, there fell a voice from heaven, “O King Nebuchadnezzar, to you it is spoken: The kingdom has departed from you,

Immediately the Lord shows Nebuchadnezzar that he does not tolerate such self-exaltation. He can no longer take it that the king of Babylon will not acknowledge him as he showed himself in the king’s dream. Nebuchadnezzar pretends that he is supreme. In doing so, he makes a claim upon God’s high throne. Straightaway God’s voice comes from heaven. Now Nebuchadnezzar hears from God’s own mouth that the interpretation of the dream that Daniel gave him a year ago will be happening to him. He is no longer king, the people will disown him, and he will live and eat like an ox. He will lose all of his power and glory, on which he had set his proud mind.