The doctrine of the eschaton is not usually included among the array of Christian and Catholic social principles. In fact, it is often thought that attention to the last things hinders the commitment and quality of the Christian’s efforts in the temporal order. This article shows why the doctrine of the eschaton in fact has profound social ramifications. To wit: One’s eternal destiny is contingent upon the Christian’s fulfillment of his task in the temporal order, and because the Christian’s final hope is not worldly that task can be carried out regardless of the cost. The article also explores a related principle, the “proper autonomy of the temporal order,” and shows how both it and the “eschatological principle” are grounded in the Christian incarnational view of reality. Finally, the article shows how these principles shed light on the role of the laity in the temporal order.