The Old Testament Canon
"\[Jesus\] said to them, 'These are my words that I spoke to you while I was still with you, that everything written about me in the Law of Moses and the Prophets and the Psalms must be fulfilled.' "
Facing the prospect of losing Europe to Protestantism, Roman Catholics convened a council to respond to the Protestant Reformers and their ideas. This gathering, the Council of Trent, met on and off from 1545 to 1563. Trent is one of the most important councils Rome has ever held, as it codified Roman Catholic dogma regarding justification, the sacraments, and other subjects.
One of the key questions Trent was tasked to answer for the church of Rome was the extent of the canon of Scripture—the list of books that the church acknowledges as divinely inspired and thus considers to be sources of theology. Against the Protestants, Trent declared that in addition to the thirty-nine books of the Old Testament that the Reformers received as Scripture, the Apocryphal or Deuterocanonical books are also canonical for the Roman Catholic Church. But in stating that Apocryphal/Deuterocanonical books such as 1–2 Maccabees, Tobit, Judith, and others are Scripture, the Council of Trent also went against church tradition. The top Bible scholars in church history, including Jerome, did not believe the Apocryphal books were Scripture, and even many Roman Catholics who attended the Council of Trent did not want Rome to declare those books canonical.
When we look to Jesus and the Apostles, it is clear that the Protestants were right. Every time Jesus and the Apostles quote from a book they regard as Scripture, they introduce the quote with a formula such as "it is written" or "Scripture says" (for example, Matt. 4:4; Rom. 10:11). Sometimes, the New Testament refers to Apocryphal books, but such books are never quoted as if they are Scripture (for example, Jude 14–15).
Today's passage shows us clearly that Jesus' Old Testament canon included only the books in our Protestant canon. He refers to "the Law of Moses and the Prophets and the Psalms" (Luke 24:44), which corresponds to the traditional Jewish canon that contains the same books as our Old Testament canon, albeit in a different order. The Law refers to Genesis–Deuteronomy. The Prophets are Joshua, Judges, Samuel, Kings, and Isaiah–Malachi minus Daniel and Lamentations. The Writings are everything else in our Old Testament; sometimes first-century Jews called this section "the Psalms" because Psalms is the largest and most famous book in the Writings.
Coram Deo
Jesus is our Lord, so if we are to be faithful to Him, we do not want to have an Old Testament canon that is any different than the one He had. The Apocryphal books can be useful as historical works and even as repositories of human wisdom, but they are not divinely inspired and cannot determine doctrine. We must derive our theology only from divinely inspired works, so let us be careful to prove all of our beliefs by the inspired Scriptures.