19:12 His eyes [were] as a flame of fire. See PNT Re 1:14.
On his head [were] many crowns. Diadems. All kingly authority is concentrated in his hands. He is King of kings.
A name written, that no man knew,but he himself. Probably the new name of Re 2:17, a name which will be disclosed to those invited to the marriage supper of the Lamb (Re 3:12).
19:12 And his eyes are a flame of fire - They were said to be as or like a flame of fire, before, Rev 1:14; an emblem of his omniscience. And upon his head are many diadems - For he is king of all nations. And he hath a name written, which none knoweth but himself - As God he is incomprehensible to every creature.
19:11-21 Christ, the glorious Head of the church, is described as on a white horse, the emblem of justice and holiness. He has many crowns, for he is King of kings, and Lord of lords. He is arrayed in a vesture dipped in his own blood, by which he purchased his power as Mediator; and in the blood of his enemies, over whom he always prevails. His name is The Word of God; a name none fully knows but himself; only this we know, that this Word was God manifest in the flesh; but his perfections cannot be fully understood by any creature. Angels and saints follow, and are like Christ in their armour of purity and righteousness. The threatenings of the written word he is going to execute on his enemies. The ensigns of his authority are his name; asserting his authority and power, warning the most powerful princes to submit, or they must fall before him. The powers of earth and hell make their utmost effort. These verses declare important events, foretold by the prophets. These persons were not excused because they did what their leaders bade them. How vain will be the plea of many sinners at the great day! We followed our guides; we did as we saw others do! God has given a rule to walk by, in his word; neither the example of the most, nor of the chief, must influence us contrary thereto: if we do as the most do, we must go where the most go, even into the burning lake.