This beginning of signs Jesus did in Cana of Galilee, and manifested (revealed) His glory; and His disciples believed in Him. John 2:11, NKJV.
Glory, doxa, Strong’s # 1391: The meanings of this word divide themselves conformably with the use of the verb dokeo (1380), to think, recognize for what a person or a thing is. Doxa can mean appearance, reputation, glory. In our text it means the recognition belonging to Jesus as revealed to His disciples by His miracles which speak of the majestic, absolute perfection residing in Jesus as well His deity.
Hebrews 1:3 equates the glory of Jesus to God’s glory, being the self-revelation of God in the economy of redemption. In this sense, future glory is the hope of Christians.
When we read in Rom.3:23 that they come short of or lack the glory of God, it means that they are not what God intended them to be. They lack His image and character.
More specifically, doxa means not the outward glorious appearance , attracting attention to the person or thing itself, but that glory shown from within (The presence of the Holy Spirit in a cracked-pot) reflecting in the appearance which attracts attention.
And the word became flesh and dwelt among us, and we beheld His glory, the glory as of the only begotten of the Father, full of grace and truth.