Priestly Source (P): Sketch
P is the Pentateuchal (and to a much lesser extent the prophetical) source most concerned with the priests, the temple, and the organization of cult, and organization in general. The bulk of the Priestly texts are found at the end of Exodus (Exodus 25-40) and throughout Leviticus and to a lesser extent Numbers (1-10) and Joshua (13-21).
There is little need to describe P as a source in any thorough manner because it has been done so many times by so many scholars. I shall therefore restrict myself to a much more humble goal - that of delineating the Priestly narrative supplementation of Pentateuchal texts in broad terms and its relationship to J's grand scheme.
P's ideology is one of order, it is therefore ironic that as a redactor of text he did not notice the symmetries of his predecessor J. The reason for this may simply have been one of expedience. The Priestly source was too much of a legal author to enhance narrative structures. The goal of P's narratival texts is largely to provide a basis for his laws. Thus, the creation of the world is in seven days is the basis for his oft repeated Sabbath law. P's flood narrative is only background for God's covenant with humanity, and accentuates the sanctity of life and the absolute prohibition in shedding the blood of another. The story of Abraham's journey to Canaan and the promise of progeny is a prelude to the covenant of circumcision. God's salvation of Israel from the Egyptians is seen as an enactment of the Abrahamic covenant, and a prelude to the more global covenant with Israel. The plague of the first born and the subsequent expulsion from Egypt is the basis for the extensive Passover laws. The journey to Mount Sinai and the succinct ten commandments are the catalyst to a much broader body of laws encompassing the whole of Leviticus and much of Numbers.
Another important feature of the P source is his copious addition of lists to the text. Many of these lists are genealogies (e.g. Genesis 5, 11, 36) but they can also be lists of stations (e.g. Num 33), cities (e.g. Joshua 14-21) and censuses (e.g. Num 1-3). The primary reason for these additions to the series of events is that they impart an authenticity and authority which cannot be conveyed through narrative. The human mind is trained to accept exact information such as is provided by the Priestly lists at face value, we are more inclined to accept the figure of 54.3% than the narrative estimation of "about half". By inundating the reader with lists, P attempts to enhance the authority of the Pentateuch and Bible and ensure that his version of events is accepted over possible alternatives.
The centrality and bulk of P's legal sections may have prevented the enhancement of J's narrative symmetries but his ideology of order did affect the way he supplemented his predecessor's work in important ways. P was a hands off redactor, and preferred to make his additions at the beginning and at the ends of narratives, thus usually preserving his predecessors' accounts - very likely because he wished to preserve the "ordered" account. Note that his creation list and his genealogical lists appear before and after the J account of creation and expulsion. Both alter our understanding of the surrounded material in important ways without being invasive (P's genealogy hides Cain's role as the father of humanity). Only when the matter was of grave importance such as in the case of the pillaging of the innocent inhabitants of Shchem did he take go into the text in a thorough way and whitewashed the whole episode. P's sense of morality and order based on dichotomy and hierarchy thus governed his supplementation just as much as it governed his legal composition.
(The Holiness Code) H
The Holiness Code was first recognized as a short body of Priestly legal texts beginning in Leviticus 19. My teacher Israel Knohl argues in his Temple of Silence for a much more extensive source and placed it chronologically after P (the Priestly Source). H popularized priestly law for the masses and functioned as an intermediary between Priestly lists and laws and Israelite History.
In Deuteronomy 34 H connects the separate book of Deuteronomy to the rest of the Pentateuch through the narration of Moses' death. H connects the Feast of booths in Leviticus 23 to the temporary domiciles erected upon the exodus from Egypt according to P. H introduces the Deuteronomistic idea of centralization of cult in Jerusalem through the narrative of the grand non-ceremonial altar erected by the Trans-Jordanian tribes (Joshua 22) which causes the Israelites to threaten these tribes with war. H fulfills J's promise to Caleb (one of the righteous spies of Num 13) regarding his inheritance in Joshua 14. As one can tell from this short unrepresentative list H is a mediator and bridger and thus has a lot in common with the final Pentateuchal redactor we refer to below as the Bridger.