Many of the books of the New Testament were written by people who lied about their identity, claiming to be a famous apostle — Peter, Paul or James — knowing full well they were someone else. In modern parlance, that is a lie, and a book written by someone who lies about his identity is a forgery.
Most modern scholars of the Bible shy away from these terms, and for understandable reasons, some having to do with their clientele. Teaching in Christian seminaries, or to largely Christian undergraduate populations, who wants to denigrate the cherished texts of Scripture by calling them forgeries built on lies? And so scholars use a different term for this phenomenon and call such books “pseudepigrapha.” Link. This is based on his book Forged: Writing in the Name of God--Why the Bible's Authors Are Not Who We Think They Are.