The unity of the book of Genesis is unmistakable; yet a close inspection reveals it to be rather a unity of idea than of execution. While in general it exhibits the gradual progress of the divine purpose on its way through primeval and patriarchal history, in detail it presents a number of phenomena incompatible with unity of authorship. The theological presuppositions of different parts of the book vary widely; centuries of religious thought, for example, must lie between the God who partakes of the hospitality of Abraham under a tree (xviii.) and the majestic, transcendent, invisible Being at whose word the worlds are born (i.). The style, too, differs as the theological conceptions do: it is impossible not to feel the difference between the diffuse, precise, and formal style of ix. 1-17, and the terse, pictorial and poetic manner of the immediately succeeding section, ix. 18-27. Further, different accounts are given of the origin of particular names or facts: Beersheba is connected, e.g. with a treaty made, in one case, between Abraham and Abimelech, xxi. 31, in another, between Isaac and Abimelech, xxvi. 33. But perhaps the most convincing proof that the book is not an original literary unit is the lack of inherent continuity in the narrative of special incidents, and the occasional inconsistencies, sometimes between different parts of the book, sometimes even within the same section. This can be most simply illustrated from the story of the Flood (vi. 5ff.), through which the beginner should work for himself-at first without suggestions from critical commentaries or introductions--as here the analysis is easy and singularly free from complications; the results reached upon this area can be applied and extended to the rest of the book. The problem might be attacked in some such way as follows. Ch. vi. 5-8 announces the wickedness of man and the purpose of God to destroy him; throughout these verses the divine Being is called Jehovah.[1] In the next section, _vv_. 9-13, He is called by a different name--God (Hebrew, _Elohim_)--and we cannot but notice that this section adds nothing to the last; _vv_. 9, 10 are an interruption, and _vv_. 11-13 but a repetition of _vv_. 5-8. Corresponding to the change in the divine name is a further change in the vocabulary, the word for _destroy_ being different in _vv_. 7 and 13. Verses 14-22 continue the previous section with precise and minute instructions for the building of the ark, and in the later verses (cf. 18, 20) the precision tends to become diffuseness. The last verse speaks of the divine Being as God (Elohim), so that both the language and contents of _vv_. 9-22 show it to be a homogeneous section. Note that here, _vv_. 19, 20, two animals of every kind are to be taken into the ark, no distinction being drawn between the clean and the unclean. Noah must now be in the ark; for we are told that he had done all that God commanded him, _vv_. 22, 18.