Some people say that that some of the writings in the New Testament are pseudepigraphal, meaning that they were written by someone other than the person identified as the author in the writing itself. This cannot be, for the reasons wisely given below. Because inclusion in the canon was based on apostolic origin, inclusion in the canon is another way of saying that a writing is genuinely apostolic. Therefore, if someone could show that an authorship claim of a writing is false, then that writing would not belong in the canon – at least for those ancients who established the canon.
As I have said before, the only reason we care about canon is because it is the way that the ancient church told us what writings they deemed to be apostolic. That some people today view canon as a prerogative of the church which does not depend on apostolicity is beside the point.
Pseudepigraphy is inconsistent with New Testament values. Therefore, pseudepigraphal writings have no place in the New Testament.
[I]f the Pastorals did not come from within the original apostolic circle, then they are no part of the authoritative exposition of the faith which Christ inspired His apostles to give for the guidance of the universal Church, and so they are not canonical….if the Pastorals are Scripture, then their claim to authorship, like all their other assertions, should be received as truth from God; and one who rejects this claim ought also to deny that they are Scripture, for what he is saying is that they have not the nature of Scripture, since they make false statements. – J. I. Packer
[A]postolic pseudepigrapha were a tainted enterprise from the start. At no point in the church’s early history could they avoid the odor of forgery. Only when the deception was successful were they accepted for reading in church, and when they were found out, they were excluded, for example 2 Peter, by the minority who regarded it as pseudonymous. In the light of these factors scholars cannot have it both ways. They cannot identify apostolic letters as pseudepigrapha and at the same time declare them to be innocent products with a right to a place in the canon. – E. Earle Ellis
If the church (and the scholars within it) is no longer willing to accept the Pastoral Epistles as written by Paul, perhaps it should, rather than creating strained theological justifications for their continued canonical presence, eliminate them as forgeries that once deceived the church but will do so no more. – Stanley E. Porter