What does Daniel 4:30 mean?

Nebuchadnezzar must have felt secure and calm as he walked on the roof of his palace. He certainly felt immensely proud. Some years prior, he had been given a dream where his kingdom was portrayed as the golden head of a statue (Daniel 2:36–38). One year before the events of this verse, he dreamed of a massive tree that was sentenced to be cut down in humiliation (Daniel 4:10–17). Daniel indicated that this was an impending judgment on the king from God (Daniel 4:24–26), calling on Nebuchadnezzar to repent (Daniel 4:27). One year later (Daniel 4:29), possibly thinking the danger had passed, the king was caught unprepared.

King Nebuchadnezzar's ego was inflated as he peered over the city and applauded himself for his success. He didn't realize that his residence was about to shift from his palace to a field (Daniel 4:28). Nor did he realize his majesty was going to vanish and be replaced with humiliation. First Thessalonians 5:3 predicts that during the end times, people will put faith in their own security, only to suffer sudden catastrophe. At the end of the tribulation another powerful ruler and restored Babylon will burst with pride, prosperity, and a false sense of peace only to see it all collapse (Revelation 17—18).