In The Primacy of Faith, Kroner tries to show that natural theology cannot be prohibited by dogmatics but also that a merely rational faith, as provided by Kant, is not tenable. According to the author, reason needs the supplement of revealed religion. As such, faith and reason do not contradict but rather complement each other. In this relationship, faith has the primacy. It surpasses the power of reason and completes its undertaking. Kroner calls this standpoint a modern conservatism. It does not inaugurate a new orthodoxy, but it shows the legitimate right of supernatural and even super-rational faith—of that faith which was and is and he trusts will ever be the basis and the source of our life. He further asserts that the tendency towards the humanization of religion is passing; it led finally to the dehumanization of humankind, and thus it refuted itself. For Kroner, faith should neither be orthodox nor heterodox; it should not be dogmatic at all. It should be universal and individual at the same time, preserving the ancient message but also reconciling it with the thinking mind of today.