Here "words" refers to a message. See how you translated this in [Revelation 22:7](../22/07.md). Alternate translation: "the prophetic message of this book" (See: [[rc://en/ta/man/translate/figs-metonymy]])
This can be stated in active form. Alternate translation: "which I have written about in this book" (See: [[rc://en/ta/man/translate/figs-activepassive]])