We argue that there is a well-intentioned—yet mistaken—definitional turn within contemporary cultural discourse in which ‘true’ religion, being essentially loving and peaceful, is distinguished from ‘false’ religion. Concerned with the possibility that this discourse might be prevalent in school Religious Education (RE), we surveyed practicing RE teachers within the United Kingdom (UK) on their beliefs about religion. We wanted to see how far the surveyed teachers evidenced a strand of contemporary cultural discourse which, we argue, conceptualizes bad religion as false religion. Responses from 465 teachers to our online survey indicate that many RE teachers understand religion(s) as essentially benign or pro-social—and present it/them as such in the classroom. We argue that RE can only foster religious literacy if religions are presented as multifarious, complex, social phenomena. This cannot be predicated upon an essentialist conceptualization of harmful religion as false religion, which is inimical to understanding religion in the world today—as in times past. We conclude that this conceptualization is a barrier to UK RE meeting both its extrinsic purpose to educate, and one of its intrinsic purposes to foster tolerance and pro-social attitudes.