“I testify to everyone who hears the words of the prophecy contained in this book: If anyone adds to them, God will add to him the plagues described in this book. And if anyone takes away from the words of this book of prophecy, God will take away his share in the tree of life and in the holy city that are described in this book.”
At the end of his prophecy, the apostle John applies a general principle to his book. Appearing as it does at the end of the canon, it also serves as a warning to the complete word of God.
How is the principle of reciprocity applied here?