Quick takeaways

• The absence of direct quotations from the Deuterocanonical books in the New Testament does not prove their non-canonicity as Jesus and the New Testament authors sometimes introduce quotations without using specific formulas like 'Scripture says' or 'it is written', indicating their regard for the source as Scripture.

• The criterion for canonicity cannot solely rely on direct quotations in the New Testament using specific formulas, as many books of the Old Testament and even several Pro-canonical books are also not quoted, and the books of the Bible were combined differently in the first century, necessitating other arguments and evidence for the inclusion of the Deuterocanonical books in the canon.

Deep dives