In this article we argue that an immaterialist ontology—a metaphysic that denies the existence of material substance—is more consonant with Christian dogma than any ontology that includes the existence of material substance. We use the philosophy of the famous eighteenth-century Irish immaterialist George Berkeley as a guide while engaging one particularly difficult Christian mystery: the doctrine of the Incarnation of Christ. The goal is to make plausible the claim that, from the analysis of this one example, there are strong reasons for thinking that if one wants to be a Christian one ought to be an immaterialist.