The relationship of theology to philosophy is much more difficult to determine, because it is much more complicated. The problems can here only be mentioned. If one understands philosophy as the discipline that attempts to explicate the totality of being, the difference between philosophy and theology becomes apparent. If theology is responsible to an authority that initiates its thinking, speaking, and witnessing—e.g., a document containing revealed truth, as well as the spiritual testimony related to it—philosophy bases its arguments on the ground of timeless evidence, an evidence with which autonomous reason understands itself to be confronted. Since, on the other hand, theology also uses reason and systematically develops its tenets—however much its critical reflections are based on religious convictions—there are many common areas that have partly complementary significance but that partly also lead to polemical tensions.

The religious significance of theology

Just as in the case of religions themselves, so also their theological reflections are not limited to a special religious sphere, separated from common life. Whoever speaks of God and the gods speaks at the same time of humanity and of the meaning of existence. He makes therewith statements about the world, its conditions of being created, its estrangement from the purpose of creation (e.g., sin), and its determined goal (eschatology, or view of the last times). Out of these statements result normative directives for life in the world, not only for the purpose of gaining salvation but also for concrete ethical behaviour in the context of the I-Thou (or person to person) relationship, of the clan, of the nation, and of society. In ancient times, all aspects of life (e.g., the relationship between the sexes, hygiene, and work, among others) were determined religiously and permeated by cultic forms and practices. In this regard, every religion contains the totality of being that its “theology” intends to express—if one also includes certain rudiments of reflection in primitive religion in the concept “theology.”

In primitive religions the tribe represents the pivot around which all worldly relations turn. The primeval (or mythical) time to which the tribe traces its own origins is also the time of salvation and fulfillment. Therefore, primitive religions primarily concern themselves with the ancestral cult. Involved in tribal concerns in the realm of religious thought are conceptions of mana (spiritual power, or force)—i.e., the teaching that tribal heads, medicine men, and sorcerers are subjects of special charisma (spiritual power or influence) and more potent powers of life. In Eastern religions, as in Western religions, this understanding is infinitely refined, developed, and theologically reflected. In regard to the relationship of humanity to the world, many Eastern religions (especially Hinduism) have a definite skeptically tinged negative view of all reality, which is especially pronounced in contrast to the Christian doctrine of creation. Although this doctrine points to a “happy event” in Christianity, the call to life and reality is understood in Eastern thought in the opposite manner. As the Scottish religious scholar and missionary Stephen Neill wrote:

To be man implies being cut off from all true reality. Creation should have never happened, and its faults should be eliminated as soon as possible.…The illusion that I am is a calamity. Not death is to be explained, but rather birth.

The cultural importance of theology

Since theology does not remain restricted to transcendent statements and to an esoteric and sacred realm, and since it rather encompasses all worldly dimensions (cosmology, anthropology, historiography, and other areas), it has always had important significance for cultural evolution and general intellectual life. Western historians hardly need to be reminded of the fact that the prophetic theology of history in the Hebrew Bible (Old Testament)—e.g., the 8th-century-bce Hebrew prophets Amos and Isaiah—decisively influenced the origins of the concept of history and, indeed, made this concept possible in the first place. A Hebrew Bible theology of history is based on the understanding of history as a linear process, as directed to a goal (i.e., the Kingdom of God) and as qualified by the characteristic of singularity. This view of history contrasts with a cyclical understanding of successive events—i.e., the view that history repeats itself. The fact that university and school were originally initiated by the church (as is still very often the case in mission fields) is based on the fact that theology has thematized in its various subjects the various dimensions of life (nature, history, ethics, and other disciplinary areas). Also, much of modern philosophy has emerged out of theological themes and categories; even in the works of Karl Marx remnants of this fact are still observable. Modern philosophy has, by and large, only gradually emancipated itself from this theological origin, but this emancipation also has taken place in a manner that has retained the dialectical relationship of theology and philosophy. That theological questions in the modern age of secularism are less openly posed than in the time of the Middle Ages does not reduce their lasting significance. They always reemerge, often in disguised form, such as in the quest for the meaning of life and existence or in the nihilistic resignation regarding that quest; furthermore, they reemerge in the quest for the dignity of human existence, the inviolability of life, the determination of human rights, and many other such questions. The German American theologian Paul Tillich investigated specifically the secular realm in view of the relevance of these latent theological questions.