How Many Books are in the Bible?

02-01-2026Weekly ReflectionJen Arnold, M.A.

Have you ever opened a Protestant Bible and wondered why it only has 66 books instead of the 73 you find in your Catholic Bible? These seven books — 1 and 2 Maccabees, Sirach, Wisdom, Baruch, Tobit, and Judith — are woven into the standard canon of the Old Testament in the Catholic Bible, while in the Protestant Bible they are separated out and viewed as historically valuable and spiritually edifying, but not divinely inspired Scripture. To get to the root of the differences, you have to take a trip through Church history, beginning with the earliest Christians and progressing through the Protestant Reformation. Let’s look at the Catholic defense of these seven books as divinely inspired Scripture and a fuller revelation of God’s wisdom.

We’ll begin by defining terms, since Catholics and Protestants refer to these books differently. As I stated before, Protestants separate these books from the others and refer to them as the Apocrypha. Apocrypha comes from the Greek Apokryptein, which means “hidden away” or “to hide away.” In the early days of Protestantism, these books were meant to be set aside for “private” study as they were not part of the accepted canon of Scripture. Catholics refer to these books as deuterocanonical. ‘Deutero-’ comes from the Greek deuteros, which means “second,” so the deuterocanonical books are the “second canon.” One common Protestant objection to these books is that Catholics added them later, as indicated by their collective name. While it is true that the books were added later than the others due to early disputes, it did not happen in the way or at the time that modern-day Protestants mistakenly argue, which I will explain later.

After the Resurrection and Ascension of Jesus, the earliest Christians were not handed a Bible or an Old Testament with a finalized “Table of Contents.” Additionally, the heavy persecutions of the second and third centuries made it essentially impossible to come together with the purpose of establishing a canon of scripture, which necessitated a reliance on oral tradition. It wasn’t until the fourth century, with the legalization of Christianity, that we began to see the early Church fathers and ecumenical councils finally discussing a set canon.

Jews also had issues with having an established canon of scripture, having various Hebrew texts across sects. Centuries before Christ, after Alexander the Great’s conquests (d. 323 BC), Greek became the dominant language. As Hebrew became more obscure, Jews in Alexandria translated their scriptures into Greek, which created a need for a more formalized canon. The outcome was the Septuagint (LXX), meaning 70, which included the protocanonical books (Genesis-Malachi) and deuterocanonical books (debated and settled at that time), like Wisdom, Sirach, and
2 Maccabees. Jesus and the apostles quoted the Old Testament over 300 times, with two-thirds of those quotations from the Septuagint. While they do not directly quote deuterocanonical books, they allude to them, signaling familiarity, and they never reject or rebuke them. For example, Hebrews 11:35 says, “Women received their dead by resurrection. Some were tortured, refusing to accept release, that they might rise again to a better life.” This echoes 2 Maccabees 7, detailing a mother’s seven sons martyred for faith, rejecting release for eternal resurrection — a story absent from the Protestant Old Testament. Early Christians, evangelized by the apostles, using the Septuagint, would have read these scriptures without second-guessing them.

Given that the Catholic Church cites Sacred Tradition as a source of authority, the deuterocanonical books were included in the debate on the canon, along with the protocanonical (“first canon”) books, because of their documented use in the early Church. The early Christian fathers clearly treated the deuterocanonical books as divinely inspired Scripture:

The Didache (c.70 AD) cites Sirach, “You shall not be double-minded or speak with a double-tongue, for to do so leads to death.” (Didache 2:4, cf Sirach 5:14)

Clement’s Letter to the Corinthians (c. 80 AD) references Wisdom, “By the word of His might He established all things, and by His word He can overthrow them. Who shall say unto Him, What have you done? Or, Who shall resist the power of His strength?” (Clement 27:5, cf Wisdom 12:12)

Polycarp’s Letter to the Philippians (c.135 AD) references

Tobit, “When you can do good, defer it not, because ‘alms delivers from death’” (Polycarp 10:2, cf Tobit 4:10).

As I said before, the Christian canon of scripture began to be formalized in the fourth century. The Council of Rome (382 AD) under Pope Damasus listed all 73 books, matching the books of today’s Catholic Bible. The Canon was then ratified at Hippo (393 AD) and Carthage (397 AD and 419 AD) and affirmed again by Pope Innocent I (405 AD). These affirmations of the canon all included the deuterocanonical books without distinction. St. Augustine also defended the full 73-book canon of scripture. While St. Jerome accepted some portions, he was initially hesitant about the deuterocanonical books as a whole, but it is important to note that he recognized that the Church alone had the authority to determine the canon, and he included them in his Latin translation of the Vulgate. He later defended this choice, recognizing humans as fallible and the Church as protected by the Holy Spirit.

Over a millennium passes, and the Protestant Reformation marks the first time in Church history, since the earliest days of Christianity, that the canon of scripture is ever brought into question. Martin Luther altered the canon, removing seven books and relegating them to an appendix (the ‘apocrypha’) in his 1534 Bible. The deuterocanonical books affirm Catholic doctrine like sacrifice and prayer for the dead, that they might be delivered from their sin (purgatory), which conflicted with his belief in sola fide (faith alone) (cf. 2 Mac 12:43-46). As more reformers emerged, and their objections persisted, some would do away with the books altogether, while others maintained them as useful but non-canonical appendices.

Now we come to the current misunderstanding that modern Protestants have of the timing of the addition of the deuterocanonical books. Martin Luther caused quite a stir in the Church with his objections. In response, the Council of Trent (1545-1563) was called. The aim was to definitively clarify doctrines against emerging heresies and to address internal abuses through Church reform. In its Fourth Session on April 8, 1546, the Council of Trent issued a definitive decree on the canonical Scriptures, affirming both the written books of the Old and New Testaments, “as contained in the old Latin Vulgate edition,” and the unwritten apostolic traditions as sources of divine revelation for faith and morals. The response also enumerated the exact books, declared them sacred and canonical “in their entirety with all their parts,” and imposed an anathema (excommunication) on those who reject them or the traditions. At this point, the Protestants were using a different canon of scripture from that listed at the Council of Trent and were consequently declared anathema by the Catholic Church. This is where the myth emerged that those seven books were added at Trent, and when the term “deuterocanonical” was mistakenly understood to mean they were “secondly” added in 1546. As we have already established, the debates had taken place much earlier, and the canon was established and reaffirmed many times prior to Trent. Trent was merely another opportunity to do the same, only in the context of a crisis in which the canon was being questioned by others. As an aside, another reason this myth doesn’t quite make sense is that, if the council added the books to the Canon in 1546, how could Luther have included them in his first 1534 Bible as an appendix prior to the Council of Trent?

As we know, the Catholic Church contains the fullness of Faith. The deuterocanonical books provide us with further evidence of that fact. They teach divine truths equivalent to those in the rest of the Bible, fostering edification and doctrine. Wisdom and Sirach emphasize fearing God, prudence, almsgiving, and friendship with the divine, while working against worldly vanities. Tobit models intercession, fasting, and filial piety. Judith demonstrates trust in God’s deliverance. 2 Maccabees defends bodily resurrection and purgatory (e.g., prayers for the dead). Baruch calls for repentance amid exile, and 1-2 Maccabees recount fidelity under persecution, prefiguring Christ’s passion. Choose one or two of the deuterocanonical books to read this week and meditate on how they add to the richness of our Catholic faith.