HERE is a Gospel sandwich. The filling is pure common sense: do not start what you cannot finish. The bread is two hard sayings: hate your family, and give up your possessions.

Luke 14.25-27 says that we must love Jesus more than family. That struck a chord with me, because I have been listening to a podcast about a cult called the Jesus Army. It is one thing to say that loyalty to family must not trump duty to God; it is another to treat rejecting one’s family as a test of loyalty. People may be pressured into giving up a hobby, or a friendship, or even a pet. They think that what is being tested is their devotion to God. What is really being tested is their devotion to the group.

This teaching of Jesus in Luke is found in two other Gospels. One is Matthew, 10.37-38 (with some variation in the details). But the other text is not Mark or John. Perhaps it appeared in Q, that hypothetical collection of sayings of Jesus which Matthew and Luke used but Mark and John did not (Q has not survived). But it can be found in an apocryphal book, the Gospel of Thomas. In this context, “apocryphal” means a book written after the Bible, not to be confused with the Apocrypha in some Bibles, which are writings from the period between the Old and New Testaments.

The Gospel of Thomas claims to be “secret sayings which the living Jesus spoke and which Didymos Judas Thomas wrote down”. It was discovered in 1945, written in Coptic, a lost form of Egyptian, in a manuscript from the fourth century. Fragments of an earlier Greek version also survive; the original text may be not much later than John.

No Bible has ever contained the Gospel of Thomas. Like the canonical Gospels, it preserves material from early times, when oral traditions about Jesus were first written down. Some scholars link the prominent part that it gives to Thomas with his unique depiction in John’s Gospel. Unlike Matthew, Mark, Luke, or John, it is Gnostic in outlook: this means that it treats truths about Jesus as esoteric secrets for a privileged few — cult-like, we might say.

In one way, the Gospel of Thomas is irrelevant to Christians: the four-Gospel canon was established by 200, long before the canon of the New Testament as a whole was closed. But it is one of several Gnostic writings that have left a mark on 21st-century Christianity through Dan Brown’s fantasy The Da Vinci Code (2003).

Twenty years ago, the internet had hardly got going as the natural refuge and breeding ground of evidence-free conspiracy theories. But Brown’s book gave a glimpse into a dystopian future that has now become reality: facts and corroboration being overtaken by fake news. Misinformation. Disinformation.

The Da Vinci Code was a trailblazer when it came to mining Gnostic pseudo-Christianity for factoids in place of facts. It treated Gnostic texts as evidence of a church conspiracy to hide historical truths about Jesus. It probably undermined many people’s faith. My then congregation, 20 years ago, included some who were worried by what they read in it, while my daughter explained to me, after an RE lesson, the “fact” that Jesus had not died, but had married Mary Magdalene.

Thank goodness we Christians have our own version of BBC Verify: the canon of scripture. It represents meticulous research intended to guarantee that Christians would not be deceived by fake teaching and pseudo-Gospels. The canon is our own quality assurance, confirmed for the Church of England in Article VI of the Thirty-Nine Articles.

There is no story of Jesus’s life in the Gospel of Thomas: just a collection of statements, blending fact and fantasy. The one that recalls Luke 14.26-27 stands beside a non-scriptural one of Gnostic origin:

Para. 55: “Jesus said: whoever does not hate his father and his mother cannot become a disciple to Me. And whoever does not hate his brothers and sisters and take up his cross in My way will not be worthy of me.”

Para. 56: “Jesus said: whoever has come to understand the world has found [only] a corpse, and whoever has found a corpse is superior to the world” (translation by Thomas O. Lambdin).

That should reassure us that, when our Christian forebears decided to set the number of canonical Gospels at four, they knew what they were doing.

(Readers can access Lambdin’s text on the Internet Archive, under “The Nag Hammadi library in English”, and see for themselves how the text merges authentic fragments from the canonical Gospels with Gnostic speculation and fantasy.)