Verse 10. "'I saw, and behold there was a tree in the midst of the earth, and its height was very great...'" It was not only of Nebuchadnezzar, King of the Chaldeans, but also of all impious men that the prophet says: "I beheld the impious man highly exalted and lifted up like the cedars of Lebanon" (Psalm 37:35). Such men are lifted up, not by the greatness of their virtues, but by their own pride; and for that reason they are cut down and fall into ruin. Therefore it is good to follow the teaching of our Lord in the Gospel: "Learn of Me, for I am meek and lowly in heart" (Matthew 11:29). But as for the fact that, according to Theodotion, he mentions his kutos or height - or else his kureia, as he himself later renders it, that is to say, his dominion (a word we have translated as "his appearance") - those same detractors of the historicity of this passage slanderously assert that Nebuchadnezzar's dominion never possessed the entire world. He did not rule over the Greeks or barbarians, or over all of the nations in the north and west, but only over the provinces of the East; that is to say, over Asia, not over Europe or Libya. Consequently all these slanders require to be understood as attributable to the devil, for actually we ourselves should accept all this as spoken by way of hyperbole, having in view the arrogance of the impious king, who in Isaiah (chap. 14) makes as great a boast as this, claiming that he possesses the very heaven itself, and the whole earth besides, as if it were a nest full of birds' eggs.
By the tree blessed Daniel said [Nebuchadnezzar] personally was depicted, and he said its height reached to heaven to suggest not the real tree but his thoughts and imaginings.… His [conceited attitude] is the reason he sees the height of the tree reaching to heaven; but since, so to say, he even had control of the whole world, he sees the tree trunk—that is, the extent of its breadth—expanding as far as the ends of the earth.
“Its top,” that is, of the tree, is his thoughts and the pride of his spirit. “Its foliage” is his army. “Its fruits” are his nobles. “The animals of the fields and the birds” are the nations and kingdoms that he has subdued. “From it all living beings were fed” are because the silver and gold that were for the benefit of people were coined by his mint. “A holy watcher” is one of the spiritual beings. “Its branches” is his dominion. “Its stumps and roots” is said because his sovereignty will last until his return. “With bands of iron and bronze in the grass of the field” are the words because when he is in the desert and feeds on vegetables, his sovereignty will stay with him in this manner, like something bound with iron and bronze.
[AD 420] Jerome on Daniel 4:10