Medieval crusade apologists condemned Islam for the very coercion Christendom practiced.

Evidence

Humbert of Romans, the apologist for the Crusade, found no difficulty in condemning Islam for aggression, or in criticising Muhammad for forcing men to follow him by the sword, where Christ had accepted only voluntary believers. The early Muslims forced Christians to become Muslim, and killed others, and Muslims have done the same ever since: ‘they are so zealous for their religion that wherever they hold power they mercilessly behead every man who preaches against their religion.’ — Norman Daniel, Islam and the West, 701

Categorization

• XREF: The asymmetry between Christ’s voluntary followers and Muhammad’s coerced ones is the medieval seed of the West’s self-constituting contrast against an Islamic outside — matches the vault’s constitutive-outside cluster.