Fountain of all knowledge,
Spring of holiness,
Zenith of all glory,
Beauty that never fades,
I will choose the path He shows me,
And be content with His judgments.
1QS, column 10. Translation from The Dead Sea Scriptures (3rd ed.) by Theodor H. Gaster, p. 138.
EDIT: I realize now that this isn’t strictly a prayer, but more of a vow made by initiants.