Peter used the title Majestic Glory as an indirect way of talking about God. The use of such oblique names for God was a Jewish custom that was adopted to avoid mispronouncing the name of God.
Majestic Glory in Greek:
Hē megaloprepēs doxa
Strong’s Concordance numbers: 3169, 1391
Bible reference: 2 Pet. 1:17
Peter recalled the transfiguration of Jesus (Yeshua‘) and the words of His Father: He received honor and glory from God the Father when the voice came to him from the Majestic Glory, saying, “This is my Son, whom I love; with him I am well pleased.” (2 Peter 1:17 NIV)
Similar names of God are: Father of glory, King of glory, God of glory, Majestic one, Majesty on high, and Majesty in the heavens. There are also similar names of Jesus: Lord of glory, Glorious Lord Jesus Christ, and Glory of Your people Israel.