Albert Barnes Commentary Daniel 4:31

"While the word was in the king`s mouth, there fell a voice from heaven, [saying], O king Nebuchadnezzar, to thee it is spoken: The kingdom is departed from thee:" — Daniel 4:31 (ASV)

While the word was in the king’s mouth - In the very act of speaking - thus showing that there could be no doubt as to the connection between the crime and the punishment.

There fell a voice from heaven - There came a voice; or, perhaps, it seemed to fall as a thunderbolt. It was uttered above him, and appeared to come from heaven. There was an important sense in which it did fall from heaven, for it was the voice of God.

Saying, O king Nebuchadnezzar, to thee it is spoken - For you it is particularly intended, or what is predicted is now spoken to you.

The kingdom is departed from thee - You are about to cease to reign. Up to this time he retained his reason, so that he might distinctly understand the source from where the judgment was to come, and why it was brought upon him, and that he might be prepared, when he should be recovered from his insanity, to testify clearly to the origin and the nature of the judgment. The Codex Chisianus has an important addition to what is said here, which, though of no authority, as having nothing corresponding to it in the original text, yet states what is in itself not improbable.

It is as follows: “And at the end of what he was saying, he heard a voice from heaven, To you it is spoken, O king Nebuchadnezzar, the kingdom of Babylon shall be taken away from you, and shall be given to another, a man despised or of no rank - ἐξουθενημένῳ ἀνθρώπῳ exouthenēmenō anthrōpō - in your house. Behold, I will place him over your kingdom, and your power, and your glory, and your luxury - τὴν τρυφήν tēn truphēn - he shall receive, until you shall know that the God of heaven has authority over the kingdom of men, and gives it to whomsoever he will: but until the rising of the sun another king shall rejoice in your house, and shall possess your power, and your strength, and your authority, and the angels shall drive you away for seven years, and you shall not be seen, and shall not speak with any man, but they shall feed you with grass as oxen, and from the herb of the field shall be your support.”