In an age of AI and with scams seeming to be everywhere, we are very aware that everything is not what it claims to be. Are you good at recognizing scams and counterfeits.  In the early centuries of the church, they also had to be able to recognize writings that were authentic and tied to the early apostles vs. those that were false. That is one aspect of the church recognizing the canon of scripture that God desired. The early church had many options to choose from.  The figure shows 33 writings that were rejected as part of the New Testament.

Think about what kind of motives someone might have had in writing a book and attributing it to someone else. Just like for authors in more modern times, a book then would have tended to sell better if it was written by someone famous, as opposed to someone that no one knew.  Perhaps some of these writers had financial motives.  Religious people have often been taken by such people.  Some may have really wanted to encourage early believers and knew that their writings would be more widely read if people thought that they were written by one of the well-known early church leaders.  Some may have been written, knowing they were speculating, a bit like a historical novel of today.  Some wrote to challenge the theology of the apostles, but chose to use names that might give their teachings credibility.

You should notice that the uncertainty bars, representing when texts might have been written, are mostly long.  Even so, only one has anyone claiming that it could have been written in the first century.  Most scholars believe that even the Gospel of Thomas was written in the 2nd century or later.  No scholars claim that it was written by the Apostle Thomas.  The Gospel of Thomas is a collection of sayings that purport to be from Jesus.  Many were taken from the NT gospels.   It also includes others that really don’t sound like the Jesus otherwise known.    Here are a couple of examples https://www.biblicalarchaeology.org/daily/biblical-topics/bible-versions-and-translations/the-gospel-of-thomas-114-sayings-of-jesus/ :

 

Jesus says: “Blessed is the lion that a person will eat and the lion will become human. And anathema is the person whom a lion will eat and the lion will become human. (7).

 

Jesus says: “Whoever will drink from my mouth will become like me. I myself will become he, and what is hidden will be revealed to him.” (108)

 

Simon Peter said to them: “Let Mary go away from us, for women are not worthy of life.”  Jesus said: “Look, I will draw her in so as to make her male, so that she too may become a living male spirit, similar to you.” (But I say to you): “Every woman who makes herself male will enter the kingdom of heaven.”  (114)

Some have questioned why only the 27 books that are in our NT have been included.  I think this figure answers that question. The set of books written in the 1st century are the primary sources of information about Jesus. The early believers understood this. They rejected books claiming to be written later by people whom they knew had been long dead. We have no reason to believe that any of these add to what we learn in the NT.