The vastness of theological interests and aspects implies that theology can master the material with which it is confronted only within a broad spectrum of partial disciplines. Since theology is based on authority (revelation), and since this authority is documented in the scriptures (especially in Christianity), it is constrained to engage in philological and historical studies of these sources and, related to these studies, also with hermeneutical (critical interpretive) questions. This historical task broadens into a concern with the history and tradition of the religion that a particular theology represents. In this concern many difficult and controversial questions arise, including whether and to what extent the canon (scriptural standard) of the sources of revelation is glossed over and modified by tradition and what normative value the modifying tradition has or should have. These problems play an important part in the relationship between Protestantism and Catholicism, even though the problems are also treated independently by each confession.

The question of truth posed by theology requires the constitution of a discipline that specifically concerns itself with fundamental questions (systematic theology). Its task can be determined in the following manner: (1) It has to develop the totality of religious teachings (dogmatics, or the doctrine of faith). (2) It has to interpret humanity’s existence in the world and, related to this, to determine the norms (ethics derived from faith) for action in the world—e.g., for one’s disposition toward fellow humans and toward societal and political structures and institutions. (3) It further has to represent its claim to truth in the context of confrontation with other claims to truth and with other criteria of verification (apologetics, polemics). As part of this concern, theology’s task is to explain reasonably, in view of historical relativism, the absolute claim of the truth that it represents. Related to this is the modern-day task of coordinating its doctrine of creation or its doctrine of the revelation of the transcendent (e.g., the Christ event in Christianity) with the worldview of modern natural science and its thesis of the immanency of being—i.e., of being that is self-contained. Another aspect of this task is the confrontation with other religions’ claims to truth, which can lead to vastly different results: either—this is noted only as an example—it can lead to the thesis of the complementary positions of individual religions and therefore to tolerance (as, for example, in Hinduism as well as in some schools in the West) or to one’s own religion’s claim to be absolute (as in Christianity, at least among the most important of its representatives). But also, in the last mentioned situation, such a claim is widely modified. It can manifest itself by a total rejection of other religions as “devil’s work,” but it can also be expressed in an interpretation of other religions as first steps to and as seeds of a religious development, the completion of which it knows itself to be.

The vast dimension of theological themes implies that theology is, with its many disciplines, a microcosmic image of the university. Even though it is a science in which the believers or the adherents of a particular religion explicate and critically analyze the truth that is represented by them, it nevertheless has to remain free within the framework of this commitment, and it has to fulfill the responsibility of its scientific task on the basis of its own autonomy. The opposite of this freedom would arise when an institution (e.g., the church) restricts the range of theological inquiry with normative claims, forcing the discipline therewith to assume ideological functions. The struggle concerning the freedom and limitations of theology—i.e., concerning responsible criticism and authority—is a struggle that has accompanied the history of theology from the very beginnings to the present.

History of theology

Origins

The term theology is derived from the Latin theologia (“study [or understanding] of God [or the gods]”), which itself is derived from the Greek theos (“God”) and logos (“reason”). Theology originated with the pre-Socratic philosophers (the philosophers of ancient Greece who flourished before the time of Socrates [c. 470–399 bce]). Inspired by the cosmogonic notions of earlier poets such as Hesiod and Homer, the pre-Socratics were preoccupied with questions about the origin and ultimate nature of the universe. The first great theologian, however, was Socrates’ student Plato, who appears also to have been the first to use the term theology. For Plato, theology was the study of eternal realities, the realm of what he called forms, or ideas. For his pupil Aristotle (384–322 bce), theology was the study of the highest form of reality, the “first substance,” which he seems to have regarded at different times as the “unmoved mover” and as “being qua being.” Aristotle spoke of three theoretical, or speculative, ways of knowing: the mathematical, the physical, and the theological, with theology being the “most honourable.”

The notion of theology as the study or contemplation (theoria) of the highest form of reality became commonplace in the Hellenistic philosophy of the Roman world in which Christianity emerged. In that world, the quest for God acquired for many people—including both Christians and non-Christians—a certain urgency, in part because of the recognized inadequacy of the traditional pagan religions and the social and political turmoil of the era. Accordingly, philosophical speculation about the ultimate nature of reality assumed a distinctly religious cast. The “lower” studies of logic and ethics and the observation of nature came to be regarded as preparatory training for communion with the divine.

These ideas very quickly found acceptance among Christian thinkers, notably the 3rd-century theologian Origen, who described the three stages in the Christian’s advance to communion with God as the ethical, the physical, and the “epoptic,” or visionary. Origen’s triad was developed by the 4th-century monastic Evagrius Ponticus, who distinguished between praktiki (ascetic struggle), physiki (contemplation of the natural order), and theologia (theology as contemplation of God). The understanding of theology as the fruit of sustained ascetic struggle, as the highest exercise of the human mind, and as prayer quickly established itself in Greek Christianity, and this interpretation is still fundamental in Eastern Orthodox theology. It is expressed succinctly in Evagrius’s oft-quoted assertion: “If you are a theologian, you will pray truly; if you pray truly, you will be a theologian.”

Alongside this sense of theology, Christians also understood the word theologia to mean the study of the divine, or the unraveling of the nature of the divine as revealed in the Bible. Christians believed that God reveals himself in the Hebrew Bible (Old Testament) through the history of the chosen people of Israel and in the New Testament through Jesus Christ, the incarnation of the Son of God. A distinction quickly developed in Christian reflection on God between theologia, strictly understood as the study of God in himself—that is, the study of God’s divine nature—and oikonomia, understood to mean the study of God’s activities in the created order, particularly the acts of creation and redemption. Because God is known only through his self-manifestation in the created order, however, the distinction between theologia and oikonomia is easily blurred. Nevertheless, it remains fundamental in Greek theology.