Mike Gantt’s question: In the 27-book NT canon that we have today, did the ancient church give us any books that they did not think were apostolic (i.e. written by an apostle or close associate of an apostle)? Conversely, did they keep out of the NT canon any books that they thought were apostolic?
In other words, does our NT canon represent what the ancient church considered to be the extant apostolic corpus?
Terry Young’s answer: Hi Mike, great question! In short, yes the 27-book canon of the NT represents what the early Church believed to be the extant Apostolic corpus, however there are some caveats to this. It is more accurate to say that the 27-book canon represents the broad ranging consensus of the ancient Church, East and West. But, many early Christians expressed heavy doubts concerning the Catholic epistles, especially Jude, II & III John, and II Peter along with Revelation. To this day many eastern Churches do not have passages from some or all of these books in their lectionaries. So, many ancient Christians advocated for a smaller corpus than 27. Others however believed some of the writings of the Apostolic Fathers should canonical, such as Clement of Rome (said to have been a disciple of Peter and Paul) or the Shepherd of Hermas, but these failed to gain wide ranging acceptance. So in short yes, but in a broad and general sense.
See the comments section in 19- We Need a Canon Don’t We? | The History of the Early Church Podcast.