Book of Enoch (1 Enoch) 103:2
Mighty One in dominion, and by His greatness I swear to you. I know a mystery And have read the heavenly tablets, And have seen the holy books, And have found written therein and inscribed regarding them:
Background and history of Book of Enoch (1 Enoch), and issues with this book.
R. H. Charles, The Book of Enoch (London: SPCK, 1917), public domain. The verse text is the English Wikisource transcription of that translation. Charles’s editorial signs are kept. He rearranges some verses in chapters 5, 39, 90, 91, and 106, so those chapters are not a straight 1, 2, 3 sequence.