Thus were the visions of my head in my bed - These are the things which I saw upon my bed. When he says that they were the “visions of his head,” he states a doctrine which was then doubtless regarded as the truth, that the head is the seat of thought.
I saw - Margin, “was seeing.” Chaldee, “seeing I saw.” The phrase would imply attentive and calm contemplation. It was not a flitting vision; it was an object which he contemplated deliberately so as to retain a distinct remembrance of its form and appearance.
And, behold, a tree in the midst of the earth - Occupying a central position on the earth. It seems to have been by itself - remote from any forest: to have stood alone. Its central position, no less than its size and proportions, attracted his attention. Such a tree, thus towering to the heavens, and sending out its branches afar, and affording a shade to the beasts of the field, and a home to the fowls of heaven Daniel 4:12, was a striking emblem of a great and mighty monarch, and it undoubtedly occurred to Nebuchadnezzar at once that the vision had some reference to himself. Thus in Ezekiel 31:3, the Assyrian king is compared with a magnificent cedar: “Behold, the Assyrian was a cedar in Lebanon, with fair branches, and with a shadowing shroud, and of a high stature, and his top was among the thick boughs.” Compare also Ezekiel 17:22-24, where “the high tree and the green tree” refer probably to Nebuchadnezzar. See the note at Isaiah 2:13. Compare Isaiah 10:18-19; Jeremiah 22:7, Jeremiah 22:23. Homer often compares his heroes to trees. Hector, felled by a stone, is compared with an oak overthrown by a thunderbolt. The fall of Simoisius is compared by him to that of a poplar, and that of Euphorbus to the fall of a beautiful olive. Nothing is more obvious than the comparison of a hero with a lofty tree of the forest, and hence, it was natural for Nebuchadnezzar to suppose that this vision had a reference to himself.
And the height thereof was great - In the next verse it is said to have reached to heaven.