This ancient prayer is based on the New Testament verses from:
+ Romans 16:27
+ Galatians 1:5
+ 1 Timothy 1:17
+ Hebrews 13:21
+ 1 Peter 4:11 In the original Greek:
Δόξα Πατρὶ καὶ Υἱῷ καὶ Ἁγίῳ Πνεύματι,
καὶ νῦν καὶ ἀεὶ καὶ εἰς τοὺς αἰῶνας τῶν αἰώνων. Ἀμήν.
Literally translated into English:
Glory to the Father, and to the Son, and to the Holy Spirit,
Both now and ever, and unto the ages of ages. Amen. The most common English translations are:
Glory be to the Father, and to the Son, and to the Holy Spirit. As it was in the beginning, is now, and ever shall be, world without end. Amen. And:
Glory to the Father, and to the Son, and to the Holy Spirit.
As it was in the beginning, is now, and will be forever. Amen. Sources:
"Gloria Patri: The History and Theology of the Lesser Doxology," by Rev. Nicholas Ayo, C.S.C., professor emeritus in the Program of Liberal Studies at the University of Notre Dame
The Catholic Encyclopedia, Volume V, (1909), Doxology (see link)