The Bible has never changed since it was written. It never will change. God will never change. That seems pretty constant to me, but I'm guessing I don't understand what you are saying.
Language is not static. It changes and evolves as its people do. This is why we have such things as High and Vulgar Latin, or Old, Middle, and Modern English, or indeed, different languages. The Bible was written in (an ancient form of) Hebrew and Greek. This was translated into Latin in the Roman Empire, and from Latin into the languages of various successor and contemporary states. To say that the language of the Bible has never changed would be patently false. If you say instead that the meaning of the words in the Bible has never changed, that is more plausible, but still troublesome to consider when you factor in the nature of translation. It is impossible to perfectly translate cultural subtext, language specific idioms, and relevant background knowledge without expanding the book twice over for notation; words in one language may have different historical backgrounds, connotations, and implications than in another, or they may even not have an appropriate substitution.
This, of course, says nothing about the hundreds of different interpretations people have laid over the Bible. That doesn't even factor into the above.