We need not worry that the NT authors occasionally cite variants or even mistranslations of the Septuagint (LXX).
Why We Should Use the Hebrew Order of the Old Testament
Which Books Belong in the Old Testament?
The word canon comes from the Greek kanon (κανων), meaning “rule.” The canon of Scripture thus refers to the rule of Scripture, identifying what is Scripture. But the issue of canon actually deals with two questions: (1) Which books belong in the Bible? (2) And what should be the order of these books?