Septuagint

The Septuagint (often abbreviated as LXX) is the ancient Greek translation of the Hebrew Old Testament, begun in Alexandria, Egypt, in the third century BC. It was the Bible of the Greek-speaking Jewish diaspora and became the primary Bible used by the early Christian Church (CCC 120).

The Apostolic Bible

The vast majority of Old Testament quotes found in the New Testament are taken directly from the Septuagint rather than the Hebrew text. Crucially, the Septuagint included the deuterocanonical books (such as Tobit, Maccabees, and Wisdom). Because the Apostles and the early Church relied on the Septuagint, the Catholic Church retained these books in her official biblical canon, whereas the Protestant reformers later rejected them in favor of the shorter Hebrew canon (CCC 120).