Mediaeval Christian polemics arose in response to real apostasy pressures under Muslim rule.

Evidence

Among Christians living under Muslim rule apostasy, both for fleshly and for worldly reasons, must have been a considerable temptation, and presumably contributed to the gradual Islamisation of Christian provinces. The criticism of it as a ‘broad way’ of perdition was bound to develop almost as soon as the Islamic state was first founded, and to have flourished wherever Islamic government obtained. — Norman Daniel, Islam and the West, 849

Categorization

• QUESTION: Worth chasing whether the indulgence-critique is causally explained by actual conversion pressures or projected entirely from theology—the author hedges with ‘presumably’ and ‘must have been’.