The critical study of the Bible had been begun in the seventeenth century by Hobbes, Spinoza, and Richard Simon, and it continued to gain momentum during the Enlightenment. In many respects the conclusions of scholars working on the Hebrew Bible were paralleled by those who worked on the New Testament, and the methods and preoccupations of both were similar to those of classical scholarship. In all three disciplines there was a growing concentration upon history. And scholars in all three disciplines recognized that historical reconstruction needed to begin with a careful analysis of sources.
This was true first of all of the analysis of the Pentateuch into several literary strands. Jean Astruc had proposed in 1753 that the different names used for God in different parts of the book of Genesis were due to different sources that antedated the final composition of the book. Astruc's insight was elaborated and refined mainly by German scholars, especially W. M. L. de Wette and K. H. Graf, who extended the analysis of sources to the rest of the Pentateuch (and in some cases to the book of Joshua, leading to the term “Hexateuch”; see below).
The results of more than a century of this source criticism were brilliantly synthesized in 1878 by the German Old Testament scholar Julius Wellhausen in his book (Prolegomena to) The History of Israel. Wellhausen's goal was to write a history of ancient Israel, especially its religion, and he followed an evolutionary model. The religion of Israel, Wellhausen argued, had developed in three stages, from a primitive, spontaneous phase in the era before the monarchy, to its high point in an ethical monotheism, from which it degenerated into a sterile legalism. To support this reconstruction, he engaged in a careful analysis of the biblical traditions, and, drawing especially on the earlier work of de Wette and Graf, gave the classic formulation to what is called the Documentary Hypothesis. According to the Documentary Hypothesis as elaborated by Wellhausen, the Pentateuch was an unreliable source for reconstructing the history of the time periods it narrated, but the traditions that comprised it, identified as J, E, D, and P, were datable and important evidence for the periods in which they were compiled. (See further “Introduction to the Pentateuch,” pp. 3–7 HB.) These “documents” were hypothetical, that is, they did not now exist, but they were the best explanation of the evidence—the parallels, repetitions, and inconsistencies in the final form of the Pentateuch.
Wellhausen's historical reconstruction is clearly a product of its time, and it reflects the biases of the late nineteenth century. His view of early Israel as a fresh, undefiled religious spirit has a Romantic flavor, and his characterization of postexilic Judaism as a decline into dead legalism has an anti‐Semitic cast. But his formulation of the Documentary Hypothesis became a classic statement, the theory that subsequent scholars up to the present have built upon, accepted, modified, or rejected. Despite initial and continuing conservative opposition, and, in the case of Roman Catholics especially, institutional interdict, it was widely adopted by liberal Protestant scholars, and eventually by Roman Catholic and Jewish scholars as well, resulting in a large consensus that is still dominant.
Source criticism was not an end in itself, but a method to be used in historical reconstruction. It recognized the inherent complexity of biblical traditions, and attempted to disentangle the prior stages of their development. Among the many significant results of source criticism was the recognition that the book of Isaiah is a composite work. The isolated insights of earlier scholars, including Rabbi Ibn Ezra in the twelfth century, and J. G. Eichhorn and others in the eighteenth, were expanded and elaborated in the commentary on Isaiah by Bernhard Duhm in 1892. The book of Isaiah, Duhm argued, was in effect an anthology spanning several centuries. First Isaiah (chs 1–39 ) was a product of the preexilic period, and was itself a composite, including authentic oracles of the eighth‐century BCE prophet Isaiah of Jerusalem, additions to those oracles and biographical materials added by his disciples, and historical narratives largely spliced in from 2 Kings. Chapters 40–55 , Deutero‐Isaiah or Second Isaiah, were a product of the mid‐sixth century BCE, as the historical references in those chapters indicated. And the remainder of the book, chs 56–66 , was to be dated a century or more later, despite similarities of language and themes to chs 40–55 . In the Romantic spirit, Duhm was motivated to distinguish the genuine words of Isaiah himself, as well as those of the anonymous prophets responsible for the latter two divisions of the book, especially the author of the “Servant Songs” (Isa 42.1–4; 49.1–6; 50.4–9; 52.13–53.12 ).
Similar preoccupations and approaches characterized the study of the New Testament. Drawing on the work of earlier scholars, especially Simon (again!) and H. S. Reimarus, in 1835 David F. Strauss published his “life of Jesus critically examined,” soon to be translated from German to English by George Eliot, in which he attempted to strip the Gospels of the miraculous and mythical in order to recover the real Jesus. This inaugurated a “quest” for the historical Jesus that continued in the work of Ernst Renan in the mid‐nineteenth century and Albert Schweitzer at the beginning of the twentieth, and that remains unfulfilled, as the lack of consensus at the beginning of the twenty‐first century demonstrates.
This quest was accompanied by a source‐critical analysis of the Synoptic Gospels. While debate about which Gospel was written first was never fully resolved, the literary priority of Mark was argued by a succession of scholars in the nineteenth century. According to this view, held by a majority of New Testament scholars but by no means all of them, Mark was used as a source by both Matthew and Luke (or, more properly, the authors of the Gospels to whom those names are traditionally given). A large number of passages in Matthew and Luke other than those based on Mark also share a verbatim correspondence, and another source was hypothesized for them. Known as Q, from the German word Quelle (“source”), it consists almost entirely of sayings of Jesus and, though hypothetical, is the earliest source for the life of Jesus. This “Two‐Source Hypothesis” was given classic formulation in English by B. H. Streeter in 1924. (See further “Introduction to the Gospels,” p. 3–6 NT.)
Source criticism in the New Testament was also applied to the Gospel of John and the Acts of the Apostles. Careful analysis of the letters attributed to Paul led to the conclusion that some of them, especially the “Pastoral Epistles” (1 and 2 Timothy and Titus), and probably Ephesians and 2 Thessalonians as well, had not been written by Paul himself, and that others (such as 2 Corinthians) may be combinations of two or more originally distinct writings.