Amidst increasing globalization and religious diversity, acknowledging and embracing openness towards religious and/or cultural others has become crucial for societal cohesion and international relations. Theological scholars, holding significant potential in mitigating inter-religious and intercultural prejudices, can play a pivotal role in addressing this challenge. However, it is acknowledged that theologians themselves may harbor such biases. This study, conducted within the framework of the Religious Openness Hypothesis, employed an online questionnaire among theology students, seen as future multipliers of religiosity, in Germany and Turkey (N = 513) using convenience sampling. The results reveal the consistent relation of religiosity to all forms of prejudice among German Christians, with a linked defense against secularism potentially leading to self-isolation and the protection of their own worldview against religious or cultural outgroups. In contrast, the (generally high) prejudice among Turkish Muslims appears to be rooted not primarily in religiosity or defense against secularism but in fundamentalism and, most likely, in other socio-cultural factors such as politics and education. For both subsamples, religiosity was positively linked with xenosophia, particularly when accounting for fundamentalism. The article concludes by proposing curriculum implications for universities and schools in both cultural contexts.

The reactivity hypothesis posits that individuals who perceive deprivation, often in the form of discrimination, may be more inclined to adopt a fundamentalist worldview and may even become more susceptible to radicalization as a reaction to these feelings of deprivation. The Uncertainty-Identity Theory posits entitativity as a moderator between deprivation and fundamentalism and radicalization, respectively. In a questionnaire study conducted on a gender-representative sample of students specializing in Islamic theology and religious education in Germany (N = 252) we found only marginal support for both hypotheses. While individual as well as collective forms of deprivation showed only a weak link to fundamentalism and no link to radicalization, entitativity demonstrated strong direct effects on fundamentalism and smaller but significant effects on radicalization. Additionally, participants who perceived deprivation against their own Muslim identity or religious practices are more likely to endorse violence against non-Muslims (‘infidels’) and as a mean to spread Islam throughout the world, but only when they perceive Muslims as moderate or highly entitative. Finally, we discuss the implications of these results for further research, university education, and counter-radicalization programs, particularly in light of the marginal effects of deprivation and the moderate to strong effects of ingroup entitativity.