Christian religiosity is linked to traditional marriage attitudes. This article jointly studies individual, contextual and cross-level effects of Christian religiosity on marriage attitudes. In doing so, this article sheds light on the issue of how a key institution like religion influences societal values. Is it only via compositional effects, with larger numbers of religious people leading to more positive marriage attitudes in a society? Or does religion also have ‘emergent properties’ that have an additional effect on marriage attitudes on top of the compositional effect? Finally, we examine whether the strength of the link between individual religiousness and marriage attitudes depends on the religious context. We use data from the ESS 2006 and use the regional level as our preferred contextual level. Our results show that Christian religiosity has individual, contextual and cross-level effects. It is level of religiosity rather than type of denomination that matters. In more religious regions, both the religious and the non-religious hold more traditional marriage attitudes. Finally, although the more religious hold more positive marriage attitudes in both low and high religious contexts, the difference between both groups is much smaller in low than in high religious contexts. This suggests that an adaptation mechanism among religious people in secularized contexts is at work.