2 Kings 16:19
"As for the rest of the history of Ahaz, what he did, is it not written in the book of the history of the times of the kings of Judah?"
Jeremiah mentions another book at 2 Kings 16:19 called the Book of the History of the Times of the Kings of Judah. This book was probably just a historical book written around the same time. Bible writers often refer to other books that were not inspired to be included in the Bible. So, while we may never know the full history of Ahaz, we can be confident that what Jehovah did include in His word is complete, in that it's got everything we need to know.
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