Influenced by the Enlightenment, the study of Christology has shifted from asking how God and human can coexist in the person of Jesus Christ to exploring the relationship between the historical Jesus and the religious ideal. For Immanuel Kant's transcendental Christology, Christ as the religious ideal has its reality only in the practical reason. The historical Jesus is only an example of that ideal in the world and cannot be equal to that ideal. In Der Christliche Glaube and Das Leben Jesu, F. D. E. Schleiermacher argues that the historical Jesus is not only the empirical example but also the religious ideal itself resulted from both the empirical and historical method.