I watched a program on the Gospel of Judas. In response to whether this noncanonical gospel is important, a priest/reverend responded with this (paraphrase): I can't imagine anyone wanting or needing more than Mark, Matthew, Luke and John. He made it seem preposterous that a noncanonical gospel would have any value or worth.
(Further detail: This priest/reverend -- whatever he's called depending on how his religious hammer hangs -- holds televised Mass or whatever you call it, and has been doing so for what seems like decades. He has full, gray hair, a not-overdone tanning-booth complexion, and great teeth... His native habitat must be a PoliGrip commercial.)
About one hundred gospels and other texts regarding Jesus (that we know of) were created in the second, third and fourth centuries. All were made for the purposes of preserving, in writing, what Jesus taught.
Aside: The stories, teachings, etc. that eventually comprised individual gospels and other texts were taught, spread, and popularized orally before they were committed to papyri. Which is to say that all gospels/other texts included in and excluded from the New Testament were guaranteed to have errors, embellishments and the like.
A game of telephone with twenty people can't pass one sentence intact.
Back to it: The reason we have MML&J in the New Testament instead of or alongside the Gospel of Thomas, Mary Magdelene and/or many others is that the Catholic Council of Hippo circa 390 chose what books, from then on, made up the New Testament. The gospels of MML&J were included, and at least twenty (gospels) were excluded.
In the program I watched a scholar stated that MML&J are the narrative gospels. They are stories: Jesus did this, did that, was crucified and resurrected. As such, the scholar noted (most likely with a British accent -- the possession of which increases one's credibility at least twofold), they are the gospels that are most easily understood.
However, MML&J contradict one another and differ in extremely important ways on extremely important things. Noncanonical texts could, possibly, help explain these contradictions and differences.
(Long example of the canonical gospels differing: Only Matthew and Luke wrote that Mary was a virgin when she conceived and gave birth. And Matt's and Luke's gospels differ in many ways many times regarding Jesus's birth.
Still, Matt and Luke began their gospels with Jesus's birth, so it makes sense that they would discuss the birth's circumstances. Mark and John began their writings with Jesus's baptism, and so don't mention Jesus's birth. Didn't bother to shoehorn in a mention of the only virgin conception and birth that ever occurred. To dedicate even one verse to something that cannot and has not been done, except in the case of Jesus and Mary, not just for humans, but virtually all multicelled organisms.)
Many of the noncanonical gospels deal mostly or wholly only with what Jesus said. The Gospel of Thomas is a perfect example: It's structure is: "Jesus said: yadda yadda yadda. Jesus said: yadda yadda yadda." Again and again, then abrupt end.
Many of these gospels do not mention Jesus's crucifixion. Far more gospels aren't concerned with Jesus's death than are. (Christianity being based largely on MML&J is, in part, why Christians celebrate Jesus the miracle man-god and freely disregard the fact that Jesus only cared about poor people and was a radical pacifist. The US's outgoing president is considered one of the most religious POTUS-es in history. Obviously: Following Jesus's example, W. got the US into a war on pretenses he knew to be false, resulting in hundreds of thousands of deaths, is bailing out financial-services firms with billions of dollars -- and those firms currently are giving employees billions of dollars in Christmas bonuses -- while allowing these firms' victims, the poor, to lose their homes -- and torturing people in violation of US and international law. Et cetera et cetera etc.)
At least one noncanonical text deals with Jesus's "missing years": the time in Jesus's life between his birth and crucifixion. Thirty years.
All of the above makes me wonder how a person like The PoliGrip Preacher possibly be satisfied only with MML&J? These four gospels disagree, contradict one another, don't account for almost all of Jesus's life, and on and on.
A priest/reverend is supposed to be an expert on Jesus's life. If a historian chooses to become an expert on Abraham Lincoln, it seems PoliGrip Preacher would suggest the historian only take into account Abe's birth and the year up to and including his death. Wanting more information would be just just plain silly.