“The book of Watchers is, with the exception of the book of Astronomy, the oldest part of 1 Enoch and the basis upon which the other sections have been built; there are allusions to it and echoes of it in the Parables, the book of Dreams and the Epistle. It is not all of one piece, but acquired its present form by a process of accretion. After an introductory section (chapters 1-5) the nucleus is formed by the story of the fall from heaven of the Watchers, i.e. angels (chapters 6-16; cp. Dan. 4:13, 17, 23).
To this has been appended an account of Enoch’s journey to the edge of the world where he sees the places of punishment of the fallen angels and the disobedient stars, as well as the range of seven mountains in the north-west, on the middle one of which is situated the throne of God (chapters 17-19).
Chapter 20, a list of the seven archangels and their functions, forms the introduction to the account of a second journey (chapters 21-36). In the first part of this journey Enoch visits places already described in chapters 17-19, and thus chapters 21-5 may be regarded as another version of the earlier journey in which the material has been reordered and expanded.
Thereafter Enoch goes to Jerusalem (chapters 26-27), and then far away to the east to the Garden of Righteousness (chapters 28-32). In the last part of the journey Enoch circles the earth and observes certain astronomical and meteorological phenomena (chapters 33-6); this material is related to the material in the book of Astronomy.
For the accounts of these two journeys the author made use of a wide range of biblical and extrabiblical traditions. In particular he drew together in chapters 21-32 a number of different biblical traditions relating to the mountain of God (cp. Ps. 48:2; Isa. 14:12-15; Ezek. 28:11-19; Exod. 24:10) and to the garden of Eden with its tree of knowledge and tree of life (Gen. 2-3).
The underlying theme, announced already in the introduction (chapters 1-5), is that of judgment. The places which Enoch is above all concerned to describe are the mountain on which God will sit when he visits the earth as judge, the place where the dead will wait until the day of judgement, and the places where the wicked (both angels and men) and the righteous will either be punished or enjoy a life of bliss.”