[Articles in the Summed Up series are intended to be summaries of chapters of selected theological books. The author(s) will be quoted verbatim for the purposes of ensuring accurate representation]
Exodus, Leviticus, Numbers
A) About the author of the chapter:
George Foot Moore “graduated from Yale College in 1872 and from Union Theological Seminary in 1877, in 1878 Moore was ordained in the Presbyterian ministry and until 1883 was pastor of the Putnam Presbyterian Church, Zanesville, Ohio.
He was Hitchcock professor of the Hebrew language and literature at Andover Theological Seminary, 1883–1902. In 1902 he became professor of theology and in 1904 professor of the history of religion at Harvard University.” 
B) Chapter Summary:
“In the early chapters of Exodus the narrative is chiefly a combination of J and E; the first considerable extract from P is Exod. vi. 2-vii. 13, recalling the covenant with Abraham, Isaac, and Jacob, and announcing its approaching fulfilment, adding, as the signature of the new epoch of the history now opening, the revelation of the name God, Jehovah (Jahveh), which none of the patriarchs had known.” 
“In the story of the plagues all three sources are interwoven; a distinctive feature of P is that Aaron with his wand, under Moses’ direction, brings the plagues to pass. The announcement of the last plague is the occasion for P to introduce the ordinance of the Passover.” 
“All the strands of the triple narrative lead to a holy mountain in the desert (Sinai in P and probably in J; Horeb in E and D), the Mount of God, represented in all as the ancient seat of Jehovah.” 
“In all the sources God’s presence is manifested by cloud and fire upon the mountain, and Moses goes to the summit to meet God (Exod. 19, J, E; xxiv. 15 b -18 a , P).” 
“… in each of the three sources at this point larger or smaller groups of laws purporting to be delivered to Moses at the holy mountain, and containing what may be regarded as fundamental institutions. These bodies of law are, however, very different; the problem of their relation to one another and to the narratives is extremely difficult, and the parallel account of the legislation at Horeb in Deut. 5 adds another element to the complication. If the reader will attentively compare Exod. 20; 21-23; 24; Deut. 5; ix. 8-x. 5; and Exod. 34, he will get some impression of the nature of the difficulties.
According to Deut. v. 22, the Decalogue (Deut. v. 6-21; Exod. xx. 1-17, with noteworthy variants) was the law written on the two tables of stone by the hand of God which Moses dashed down and shattered when he saw the people wantoning around the golden calf (Exod. xxxii. 19). God proposes to reproduce the law on two new tablets (xxxiv. 1), but the Decalogue (xxxiv. 28) written on these tablets (xxxiv. 14-26) is wholly different from that of Exod. 20, being not a compend of moral law, but prescriptions for the festivals and ritual rules, whereas Deut. ix. 8-x. 5 says in so many words that it was the Decalogue of v. 6-21 which was restored.” 
“[The problems] arise in part from the attempt to harmonize radically different representations of what the fundamental law given at Sinai (or Horeb) was, in part from the tendency of later times to ascribe to the original Mosaic legislation the whole body of actual law regarded as having a religious sanction.” 
“The fundamental law of J, the basis of the original compact between Jehovah and Israel, is preserved in Exod. xxxiv. 1-5, 10a, 14-28 (with some manifest amplifications in vss. 15, 16, 24). When this was combined with the story of the golden calf and the broken tables (E), it was necessary to take it as a renewal of the law, and this was accomplished by very slight additions in vss. 1 and 4 (“like unto the first,” “that were on the first tables, which thou brakest”).” 
“According to [P’s] theory all the ordinances of worship were revealed at Sinai. Legitimate sacrifice presupposes one legitimate temple and altar, a legitimate priesthood, and a minutely prescribed ritual. In J and E the patriarchs set up altars and offer sacrifice in many places; it is an obvious interest of the authors, or of the local legends of holy places which they follow, to trace the origin of the altars, sacred stones, holy trees and wells, at Shechem or Bethel, Hebron or Beersheba, to one of the forefathers. In P, on the contrary, the patriarchs never offer sacrifice. Until the tabernacle was erected and God’s presence filled it, until Aaron was consecrated as priest, until the technique of the various species of offering had been revealed by God and exemplified by Moses or Aaron, no sacrifice could be anything but impious, like the worship of heathen.” 
“Lev. x. 1-7 is closely connected with cc. 8-9, and its sequel (combined with other matter) is found in c. 16, the ritual of atonement. Lev. 8-9 is a good specimen of the author’s method. In the form of a description of the sacrifices of consecration and the inaugural sacrifices of Aaron, he gives a paradigm for every variety of offering.” 
“… we find in Lev. 1-7 a collection of such laws, some of them (e.g. Lev. 1 and 3) unquestionably old both in substance and formulation, with slight adaptation to their surrounding (e.g. “the sons of Aaron,” i. 5, etc.), or with supplements to meet new economic and social conditions, such as the burnt offering of doves (Lev. i. 14-17, cf. vs. 2); others are younger or have been more extensively enlarged and amended. The chapters thus represent a growth in actual custom and corresponding rule.” 
“Lev. 11-15, on various forms of uncleanness and the prescribed purifications, to which x. 10 f. seems to be a fragmentary introduction, have no obvious association with anything in the context, though they are introduced appropriately enough before the general purification of the Day of Atonement, c. 16. The laws, which read like the chapters of an exactly formulated code of purity, have been expanded by the addition of new paragraphs (e.g. Lev. xiv. 21-32, 33-53), and in some cases changes in the ritual may be recognized; compare, for example, Lev. xiv. 1-8 with vss. 10-20.
Chapters 17-26 form a distinct body of law, having certain marked peculiarities of its own, notably the frequent recurrence of the motive of “holiness”—that is, the avoidance of things and actions tabooed by the religion of Israel—often coupled with the appeal to God’s holiness, as in xix. 2, “Ye shall be holy, for I, Jehovah, your God, am holy,” or simply asserting his authority, “I am Jehovah.”” 
“The hypothesis which seems best to explain the phenomena is that an independent collection of laws (or rather the remains of such a collection), characterized by the motive of holiness, has been expanded and edited in the spirit and manner of the priestly legislation, while some laws which were originally included in this collection have been transposed to other contexts.” 
“The laws in Numbers present the same variety as in Leviticus. There are old laws with modifications and enlargements, and many others which by various signs betray a more recent origin. Num. 28-36 belong as a whole to the latter class; cc. 28 f. exemplify that growth of the law by the formulation of sacerdotal ideals or desiderata which has been noted in the case of Lev. 4. It is to be observed that the narrative of P has reached in Num. xxvii. 12-23 the end of Moses’ career; nothing is in place after it but the ascent of Mt. Abarim and Moses’ death (Deut. 34). Num. 28-36 thus stand even formally in the place of an appendix.” 
“The narrative of P (Origin of the Religious Institutions) and the great mass of ritual and ceremonial laws in the three middle books of the Pentateuch are often called collectively the Priests’ Code.” 
“… many critics—except for the orderliness, which nobody has ventured to affirm, and with allowance for later additions—regard the Priests’ Code as such a law book, compiled and edited by priestly scribes in Babylonia, brought to Judæa by Ezra, with the authority of the Persian king, to reform the many disorders that existed there, and ratified and put in force in B.C. 444 by the magnates and the people of the Jews. (See Ezra 7; Neh. 8-10, and below, pp. 129 ff.)” 
“The phenomena we have observed in Exodus-Numbers suggest the hypothesis, rather, that various old laws, dealing chiefly with sacrifice and with the rules of clean and unclean—the two principal subjects of priestly regulation—were inserted at suitable points in the Origins of the Religious Institutions (P); these received amendments and supplements both before and after their incorporation; other more independent developments, whether representing actual custom or sacerdotal aspirations, found place among or beside them; and thus the whole Priestly stratum grew by a process of accretion through many generations into its present inorganic magnitude.”