God taught Nebuchadnezzar to know that he was nothing and that the mighty God, who gives the kingdom of men to whomever He wills, is everything.

The book of Daniel covers three crucial matters: God’s heavenly rule, the preeminence of Christ, and the destiny apportioned by God for His people. In His economy God administrates the universe, including all the kings and kingdoms on the earth, in order to fulfill His purpose, which is that Christ should be preeminent in all things (Col. 1:18). For Christ to be preeminent, God needs a chosen people to coordinate and cooperate with Him. Under the rule of the heavens, everything is working together for the good of God’s elect for the purpose of making Christ preeminent (Rom. 8:28-29).

God gave Nebuchadnezzar twelve months to repent. However, Nebuchadnezzar was void of the capacity to know God inwardly, and nothing within him was touched. Hence, there was no repentance and no change; rather, Nebuchadnezzar was filled with pride (vv. 30, 37; 5:20) and thus came under God’s judgment (Prov. 16:18; 1 Pet. 5:5).

According to his nature and his being, Nebuchadnezzar was not a man but a beast. For this reason, his heart was changed from that of a man’s, and a beast’s heart was given to him (v. 16). God also took away his human reasoning (cf. v. 34).

The expression seven periods of time may refer to seven weeks, to forty-nine days.

Lit., my reason. So also in v. 36. Because beasts walk on four legs, they look down, but humans walk on two feet and look up. Nebuchadnezzar’s reasoning came back as soon as he looked upward toward the heavens. Because he had changed, his reasoning returned.