(1.) They are not once quoted by the New Testament writers, who frequently quote from the LXX. Our Lord and his apostles confirmed by their authority the ordinary Jewish canon, which was the same in all respects as we now have it.
(2.) These books were written not in Hebrew but in Greek, and during the "period of silence," from the time of Malachi, after which oracles and direct revelations from God ceased till the Christian era.
(3.) The contents of the books themselves show that they were no part of Scripture. The Old Testament Apocrypha consists of fourteen books, the chief of which are the Books of the Maccabees (q.v.), the Books of Esdras, the Book of Wisdom, the Book of Baruch, the Book of Esther, Ecclesiasticus, Tobit, Judith, etc.
The New Testament Apocrypha consists of a very extensive literature, which bears distinct evidences of its non-apostolic origin, and is utterly unworthy of regard.