Medieval Christian authors faked convert status to lend their polemics authority.

Evidence

The Contrarietas claims to be written by a convert from Islam, but it seems to me to be possible that it is really by a Christian who wished to give it greater authority by such a fictional claim. It is often difficult to imagine that a convert, however much he hated his old religion, could take just the line that the author of this work takes; and the Mecca pilgrimage that he claims to have made is particularly unconvincing. — Norman Daniel, Islam and the West, 92

Categorization

• SEED: A credentialed-critical-insider trope in medieval anti-Islamic polemic — angle for an essay on how ‘I was one of them, now I know the truth’ (converts, ex-Muslims) has functioned as an authority device for over a millennium.
• XREF: Connects to the vault’s interest in how ‘authentic insider’ voices get mobilized to construct Islam as the West’s outside.