Discussions of everyday Islamic religiosity commonly distinguish two distinct forms of Muslim religiosity, one 'normative' and 'formal,' the other 'accommodative' and 'informal.' It is invariably the latter form that is identified as the site of engagement with other religious traditions. This paper sets out to question the common association of 'popular' Islamic religiosity with 'syncretism' by analysing the methods by which Muslims defend contentious practices in everyday life. Drawing on fieldwork among Tamil-speaking Muslims in India and Southeast Asia, various strategies for defending contentious practices will be analysed, most important among which are references to Islamic scripture and scholarly tradition. Concomitantly, the discourse surrounding the defence of contentious practices and beliefs shows a heightened concern with authenticity, resulting in an often stridently anti-syncretic rhetoric. Finally, the paper will deal with an alternative way of defending contentious practices particularly salient in Southeast Asia, which tries to remove contentious practices from the sphere of 'religion' to that of 'culture.' In all cases, the respective defensive strategies clearly inhabit the same discursive space as the criticism levelled at contentious practice, revealing the problematic nature of the assumed binaries of Muslim religiosity. [ABSTRACT FROM AUTHOR]