The Gnostic Gospels is a collection of about 54 ancient texts based upon the teachings of several spiritual leaders, which were written from the 2nd to the 4th century AD. The sayings of the Gospel of Thomas, compiled circa 140, may include some traditions even older than some of the gospels of the New Testament, possibly as early as the second half of the first century. These gospels are not part of the standard Biblical canon of any mainstream Christian denomination, and as such are part of what is called the New Testament apocrypha. Recent novels, films, and video games that refer to the gospels have increased public interest.