There are three answers to this question, each dependent upon its context.
1. The logic puzzle: Question: What weighs more, a pound of bricks or a pound of feathers? Answer: They're the same; a pound is a pound. Question: Which books that are not in the Bible are Biblical texts? Answer: none of them. If they're not in the Bible, they're not Biblical texts.
2. The base reference. Before a group of people begin a game of Scrabble, they agree on a particular dictionary or word list as the final determinant of what constitutes a valid word. Similarly, with so many versions of the Bible, in order to facilitate discussion, often one particular version is selected as the context for discussion. Personally, I use KJV as my go-to version unless another version is specified beforehand. Anything not in the KJV is normally not considered Biblical ... although I realize that this answer will infuriate certain Christians, especially certain orthodox sects.
3. The question of faith. Your question really is one of faith, i.e. what someone believes is the
Word of God and uses as a basis for his personal faith. I am an atheist, and as such, I don't reference the Bible for any theistic doctrine. Instead, just as the manner in which I select the KJV as my base reference version in the preceding point, I outsource my theism interpretations to gfm7175, i.e. I go with whatever he says something means or how something should be interpreted. So for this answer, we'll have to wait until gfm7175 tells me what answer I should give you, then I'll give you that answer as my definitive answer.
@gfm7175 re: Tinkerpeach's question above. I'm on tap to provide an answer and I'm outsourcing to you. What is the correct Christian response?
@Into the Night - I'd be interested in your thoughts as well.