Faced with claims for recognising religious diversity, liberal European democracies have shifted in the last 10 years towards a more restrictive view of integration. This paper seeks to make a contribution to this line of research on how European countries deal with migration-related ethnic and religious diversity today by investigating the case of a southern country, notably Greece. Greece is an interesting case to study: it has by now 20 years of experience as a host country, but still its migrant integration policies are under-developed. In addition Greece it is currently experiencing an acute economic crisis while irregular migration towards the country is on the rise. These developments have contributed to bringing migration on to centre stage in political discourse with a concomitant rise of racist and xenophobic discourses against migrants. This paper takes, as a case study, the public Muslim prayer that took place in several squares of Athens on 18 November 2010 as a peaceful protest against the fact that Athens still does not have a formal mosque. We use this event as an opportunity for interviewing social and political actors directly or indirectly involved in it on their views regarding migration, religious diversity and their accommodation in the Greek public space. We analyse their discourse on whether and under what conditions religious diversity, Islam in particular, should be tolerated or accepted in Greek society. We propose here the notion of ‘nationalist intolerance’ to make sense of Greek discourses and propose a dynamic understanding of tolerance and intolerance as concepts that do not emanate from abstract norms but are rather negotiated in specific contexts.