Thanks for your reply.
Revelation 22:18 is usually interpreted to mean changing scripture - some would say it refers only to Rev. ("the prophecy of this book") since the "book" we know as the New Testament (a collection of "books") was not yet in existence.
That aside, if you interpret it to not adding to scripture, I don't see how your preacher (or any religious writer) wouldn't be violating if you use it in that manner.
Perhaps we're not defining "sola scriptura" the same way; might help if you told how you use the term.
best regards...
My interp is just what it says "scripture alone". Maybe I do have it wrong and I'd like to know. Thanks.