A friend and I were discussing the truth claims of Christianity and reliability of the gospels, and she made the statement that the “gospel” that was recently discvered that talks about the marriage of Mary Magdalene and Jesus pre-dates the four canonical gospels. I didn’t know if that was true or not, but I doubted that it was.
So I challenged her statement and said I’d look it up. Here’s what I found in a cursory search on the internet:
First of all, The (so-called) Gospel of Philip does not say that Mary Magdalene and Jesus were married, but it is the source for Dan Brown’s fictional account of that marriage.
The book’s origins can be traced to the Gnostic community that arose several years after the death of Valentinus (c. 160); written more than a century after Jesus walked the earth, the book cannot represent eyewitness testimony about him. Some of the brief excerpts found in Gospel of Philip may stem from the early second century; however, the date of the final form of the book is closer to the late 200s. ~The Truth About Da Vinci
See also here, here, and here, all sources, Christian and non Christian which place the composition of The Gospel of Philip later than 100 AD.
As for the canonical gospels, F.F. Bruce says in his book The New Testament Documents: Are They Reliable?:
The New Testament was complete, or substantially complete, about AD 100, the majority of the writings being in existence twenty to forty years before this. In this country a majority of modern scholars fix the dates of the four Gospels as follows: Matthew, c. 85-90; Mark, c. 65; Luke, c. 80-85; John, c. 90-100.4 I should be inclined to date the first three Gospels rather earlier: Mark shortly after AD 60, Luke between 60 and 70, and Matthew shortly after 70. One criterion which has special weight with me is the relation which these writings appear to bear to the destruction of the city and temple of Jerusalem by the Romans in AD 70. My view of the matter is that Mark and Luke were written before this event, and Matthew not long afterwards.
But even with the later dates, the situation is encouraging from the historian’s point of view, for the first three Gospels were written at a time when men were alive who could remember the things that Jesus said and did, and some at least would still be alive when the fourth Gospel was written.
None of the above settles once and for all whether the Christian gospels are historically accurate nor whether the so-called Gospel of Philip has any truth in it, but it should settle the matter of whether or not the Gnostic Gospel of Philip predates the canonical gospels. It doesn’t.