This article concerns the 'living' landscape inhabited by Sasak Muslims on the Indonesian island of Lombok, viewed in the context of reformist efforts to 'purify' local Islamic ritual practice. Drawing on the author's fieldwork in Central Lombok, the article centres on a dramatic episode that occurred in 1997 when a lightning strike caused a large tree to collapse over the graves in the village cemetery. I argue that the ways in which people 'read' this event reveals that local Muslims have different understanding of the agentive forces operating in the world,and that these understandings are expressed in changing ritual practices. Ancestors and forces in the landscape are divested of agency by Muslim reformers, who seek to disentangle the 'spiritual' from the 'material'. Yet the form of Islam embraced by these reformers also allows for a resacralisation of the local landscape.