How has the publication of the Dead Sea Scrolls affected our understanding of the history of the biblical text? Make sure to include discussion of both the Hebrew Bible and Septuagint(s).
Until 1947 with the findings of the first Dead Sea Scrolls, the witnesses to the biblilcal texts were described as having an “internal hierarchy.” This meant that the Masoretic text, the Samaritan Pentateuch and the Hebrew Vorlage of LXX was given central importance, and all other textual witnesses had a subordinate relation to one of the three mentioned above. These subordinate witnesses were termed recensions.
Thus the Torah was conceived of as an entity of three text types (or, also recensions): MT, SamP and LXX, and so these three were conceived as “axes around which other texts formed three distinct groups.” (Tov, 155).
The texts of Prophets and Hagiographa were perceived in the same manner, albeit only with two central text types (no SamP). Tov underlines that “theories, descriptions and terminology” changed with different schools and generations of scholars, but the essential notion that the textual witnesses were concentrated in three (or two) groups, pretty much remained the same. (Tov, 156)
With the findings of the Dead Sea Scrolls, this same tripartite division of textual witnesses continued for some time, and the first publications of the DJD reflect this view. The manuscripts found were still divided into which groups they were perceived at belonging to. Even though most Qumran manuscripts belonged to the MT group, all three groups were nonetheless attested in the Dead Sea Scrolls.
Emanuel Tov: Textual Criticism of the Hebrew Bible, Fortress Press, Minneapolis, 2012