According to the Documentary Hypothesis, also called the Wellhausen Hypothesis, the Torah (the first five books of the Bible) were drawn from four separate narratives and were later combined into a whole by redactors, or editors. The evidence for this hypothesis comes from the literary analysis of the Torah, including an analysis of the different names used in the Torah for God ("YHWH" or "Yahweh" or "Elohim") and repeated stories, or "doublets." Many scholars have come to believe that there were four sources of the Torah--"J" or the "Yahwist" source; "E" or the "Elohist" source; "D" or the Deuteronomist; and "P," or the Priestly source. These sources are thought to have written in order, from "J" to "P," in the period c. 950 BCE to c. 500 BCE. Each source is thought to have a different style. One of the doublets in Genesis is the creation story in Genesis 1 and the repeated story of creation along different lines in Genesis 2. In Genesis 1, the story of creation is described in seven days, but in Genesis 2, the story of creation is described with Adam and Eve's fall from grace in the Garden of Eden. In addition, the narrative of the flood, in Genesis 6-9, is given in different and at times contradictory accounts and described in repetitive ways.
Genesis 1-11, therefore, cannot be read as a coherent narrative, as it has many contradictions and duplications. The benefit of literary analysis applied to the Torah is that it allows scholars to understand the history of Judaism, including its changing nature. For example, many scholars have hypothesized that there was a growth in priestly power over the course of time, as "P" is thought to be the last source. However, many religious figures and institutions continue to believe in Mosaic authorship of the Torah--that is, that Moses wrote the Torah when he received it by God. Believing otherwise is contrary to Orthodox Jewish faith and to the beliefs of some Christian churches.