As regards the textual differences between the Greek and the Hebrew Bible, Jerome based his translation on the Hebrew text. For the deuterocanonical books, he was generally content to correct the Old Latin (translation). From this time on, the Church in the West recognised a twofold biblical tradition: that of the Hebrew text for books of the Hebrew canon, and that of the Greek Bible for the other books, all in a Latin translation.
Based on a time-honoured tradition, the Councils of Florence in 1442 and Trent in 1564 resolved for Catholics any doubts and uncertainties. Their list comprises 73 books, which were accepted as sacred and canonical because they were inspired by the Holy Spirit, 46 for the Old Testament, 27 for the New. 36 In this way the Catholic Church received its definitive canon. To determine this canon, it based itself on the Church’s constant usage. In adopting this canon, which is larger than the Hebrew, it has preserved an authentic memory of Christian origins, since, as we have seen, the more restricted Hebrew canon is later than the formation of the New Testament.
19. To the Jewish Scriptures which it received as the authentic Word of God, the Christian Church added other Scriptures expressing its faith in Jesus, the Christ. A study of these relationships is indispensable for anyone who wishes to have a proper appreciation of the links between the Christian Church and the Jewish people.