^19:12And His eyes are a flame of fire, and upon His head are many diadems; and He has a name written upon Him which no one knows except Himself.

Continuing from the previous verse:

And

3. HIS EYES are a flame of fire, and

   It is Jesus' EYES that test our faith. The result will be that we may give praise and honor and glory at this time (1 Peter 1:3-7-9). We know that this was the physical attribute given to HIS EYES in Revelation 1:14, but clearly this set of verses here in chapter 19 is spiritual in nature. The spiritual side is totally open to Jesus. On earth we can be a fake Christian, acting the part in church, and being a model to those around us, and yet, when Jesus' EYES pierces into/through us, He will judge the thoughts and intentions known only to us (we falsely believe). We may have hidden that secret self from those around us but not from Jesus (Hebrews 4:12-13).

4. upon HIS HEAD are many diadems; and

   Contrast this with what the dragon (Revelation 12:3) and the Beast (Revelation 13:1) wore on their head(s). "Many" implies more diadems than any other. Jesus is imbued with royal dignity. How different this is from the crown of thorns (Mark 15:16-20).

   There is an account in the Old Testament of the conquering king removing the crown from the conquered king and placing it upon his own head (2 Samuel 12:26-30-31). In a spiritual sense, this finalizes the fall of the kings of the earth who committed acts of immorality and lived sensuously with her (the harlot - global economic materialism, Revelation 18:9). Perhaps these diadems symbolize Jesus' final conquest over the kings of the earth.

5. HE has a NAME written upon HIM which no one knows except HIMSELF.

   Contrast this with the many blasphemous names the harlot took for herself (Revelation 17:3). Without a name, it is hard to brag or boast. That's important to the devil, you know. He feels he should be the one riding out of heaven on the white horse (previous verse).

   The name is written upon Jesus presumably by God the Father. Its meaning is hidden from us. Some scholars believe that at some time, we believers will know what that name is, just as mysteries of God had been revealed to some of the apostles (Ephesians 3:1-4-13). However, it really is immaterial whether we will get to know that name. What is important is that we now know "JESUS" and accept him as our Lord and Savior here and now.