The New Testament canon was decided by political councils that suppressed other gospels — like Thomas, Judas, and Mary — that offered different, often more esoteric portraits of Jesus, meaning the 'official' Bible reflects the winners of a power struggle, not the most historically accurate texts.

Why people find it persuasive

There really were other early Christian texts calling themselves gospels, and church authorities really did exclude them and sometimes order their destruction — that pattern looks less like discerning truth from error and more like consolidating one faction's theological and institutional power.

Important distinctions

• • Gnostic 'gospels' written in the 2nd-4th centuries vs. the four canonical Gospels written in the 1st century within living memory of eyewitnesses.
• • A council imposing an arbitrary decision vs. a council formally ratifying criteria and consensus that had developed organically over centuries.
• • Exclusion for political reasons vs. exclusion for failing well-established, independently reasonable criteria (apostolic origin, early and widespread use, doctrinal consistency).
• • 'Suppressed' in the sense of forcibly destroyed and hidden from history vs. simply not achieving the wide liturgical use and recognition the canonical texts already had.

Christian response

• • The chronological gap is decisive: the four canonical Gospels are dated by the overwhelming majority of scholars (including skeptical ones) to roughly AD 65-95, within the living memory of eyewitnesses and their immediate students, whereas the Gospel of Thomas is dated (at the earliest end of scholarly estimates) to the early-to-mid 2nd century and more commonly the mid-to-late 2nd century, the Gospel of Judas to the mid-2nd century, and the Gospel of Mary similarly to the 2nd century — a full century or more removed from the events, well after eyewitnesses had died, which is precisely the kind of gap that made these texts unsuitable as reliable historical sources by the standards the early church itself explicitly applied.
• • The criteria used to recognize (not invent) the canon were not arbitrary political preferences but had been developing organically and consistently for two centuries before Nicaea (which, contrary to popular myth, did not decide the canon at all) — apostolic origin or direct apostolic association, consistency with the 'rule of faith' taught across geographically dispersed churches, and, most tellingly, widespread and long-standing liturgical use across the early Christian world independent of any central authority; by the time of Origen (early 3rd century) and Eusebius (early 4th century), the four Gospels and the core Pauline letters were already treated as settled and universally received well before any council formally listed them, while the disputed 'gospels' had never achieved comparable widespread acceptance.
• • The content of the Gnostic gospels themselves gives good independent reason for their exclusion beyond mere lateness: Thomas is a sayings collection embedded in a Gnostic theological framework alien to first-century Jewish messianic expectation (denying the goodness of the material world, a hidden secret-knowledge soteriology very different from the Jewish-rooted, publicly proclaimed gospel of the canonical texts), and texts like the Gospel of Judas or the Infancy Gospel of Thomas contain theologically and stylistically implausible material (a young Jesus killing a playmate with a curse, elaborate 2nd-century Gnostic cosmological speculation) that reads as clearly later legendary and doctrinal development rather than early historical memory.
• • 'Suppression' is also often overstated as a historical narrative: these texts were not hunted down and destroyed the moment they appeared — many circulated for generations, were known and explicitly discussed (and rejected, with stated reasons) by writers like Irenaeus as early as around AD 180, well before any imperial involvement in Christianity existed at all, which shows rejection on textual and theological grounds, not merely political power, drove their exclusion from mainstream use long before Constantine or any council had the power to suppress anything.
• • It's also worth noting the canon-formation process was remarkably decentralized and slow rather than a single top-down imposition — different regional churches (Eastern, Western, Syriac) had slightly different disputed-book lists (over books like Hebrews, Revelation, or James) for generations, converging gradually through widespread grassroots usage and theological argument rather than a single council's fiat, which is hard to square with a simple 'political suppression' narrative implying a top-down power grab.

Christian counterresponse

Even scholars sympathetic to Gnostic materials (e.g., Elaine Pagels) generally do not claim Thomas or Judas offer a historically superior picture of the itinerant Jewish teacher of Nazareth; they argue these texts reveal the diversity of early Christian belief and practice, which is a different and more modest claim than 'these are equally or more historically reliable about Jesus.' And doctrinal consistency is not obviously an illegitimate criterion when the question is which texts accurately preserve what the apostles who knew Jesus actually taught — checking new claims against an already-established, independently-verified body of apostolic teaching is a reasonable historical-theological method, not mere power politics, especially given how early and widely the core four Gospels had already achieved recognition on independent, non-coerced grounds.