In Psalm 24, David asks "Who is the King of Glory?"
The earth is the Lord's, and the fulness thereof; the world, and they that dwell therein. For he hath founded it upon the seas, and established it upon the floods. Who shall ascend into the hill of the Lord? or who shall stand in his holy place? He that hath clean hands, and a pure heart; who hath not lifted up his soul unto vanity, nor sworn deceitfully. He shall receive the blessing from the Lord, and righteousness from the God of his salvation. This is the generation of them that seek him, that seek thy face, O Jacob. Selah. Lift up your heads, O ye gates; and be ye lift up, ye everlasting doors; and the King of glory shall come in. Who is this King of glory? The Lord strong and mighty, the Lord mighty in battle. Lift up your heads, O ye gates; even lift them up, ye everlasting doors; and the King of glory shall come in. Who is this King of glory? The Lord of hosts, he is the King of glory. Selah (Psalm 24:1-10).
David also tells us that the King of Glory is the Lord of Hosts. Then Isaiah tells us the Lord of Hosts is the "I am the first, and I am the last";
Thus saith the Lord the King of Israel, and his redeemer the Lord of hosts; I am the first, and I am the last; and beside me there is no God. (Isaiah 44:6).
Then in Revelation 1, in bold red letters Jesus reveals that He is "the first and the last":
And when I saw him, I fell at his feet as dead. And he laid his right hand upon me, saying unto me, Fear not; I am the first and the last (Revelation 1:17).
Thus making Jesus the Lord of Hosts, and therefore, the King of Glory.
Glory in the Old Testament is kabowd (kä·vōde') H5319, and in Psalm 24:7,8,9,10 we could readily use synonyms like "majesty" or "splendor" i.e. the King of Majesty, the King of Splendor. In the New Testament, the word is doxa (do'-ksä) G1391. Vines definition is "an opinion, estimation, repute; in the NT, always good opinion, praise, honor, glory, an appearance commanding respect, magnificence, excellence, manifestation of glory".
We should always remember that God manifested himself in the flesh (John 1:1, 14, 1 Timothy 3:16) as Jesus Christ or as Vine suggests "the manifestation of glory".
The Apostle Peter instructs us that because of our knowledge of who Jesus Christ is, our Lord and Savior (and now can add the King of Glory), we need to grow in His grace, giving Him all of the glory, now and forever:
But grow in grace, and in the knowledge of our Lord and Saviour Jesus Christ. To him be glory both now and for ever. Amen (2 Peter 3:18).
And let us not forget that when we get to heaven we will see that His glory makes the heaven shine:
And the city had no need of the sun, neither of the moon, to shine in it: for the glory of God did lighten it, and the Lamb is the light thereof (Revelation 21:23).