Another frequently cited source of symbolism within the book of Revelation is the various uninspired Jewish apocryphal writings:
Symbols and other suggestions are derived very frequently from the Old Testament, sometimes from common Hebrew folk-lore, and in some instances apparently from apocalyptic sources not preserved to us. There are passages in which critics are probably right in finding traces of the influence of some unknown apocalyptic writing.1
[The assumption of the two witnesses] into heaven (Rev. Rev. 11:12+) accords with that of Elijah (2K. 2K. 2:11), and with that of Moses as stated in The Assumption of Moses, mentioned by Clement of Alexandria and Origin. In this instance the Revelation seemingly assumes the familiarity of its readers with apocryphal literature.2Beckwith says that John incorporates common Hebrew folk-lore (non-truths) and bases meaning upon material which is unknown and in any case is not available to us. From the similarity of the ministry of one of the two witnesses with that of Moses, Tenney infers one must be Moses and therefore the reader is assumed to be in need of information from The Assumption of Moses to understand this fact. These are claims which are quite out of proportion with the hard evidence. Most often, our inability to understand some symbol in the book is not based upon the unavailability of an unknown apocalyptic writing, but our ignorance of the Old Testament. Further, familiarity with The Assumption of Moses is not required in order for one of the two witnesses to be Moses. Not to mention that there are reasons for supposing that neither of the two witnesses is Moses himself, but other Jews yet to be born.
There is no evidence that any one of [the noncanonical apocalypses] has served him as a source; coincidences between the work of John and the extant Jewish books are nearly limited to minor points connected with the imagery and diction. Under the circumstances it is more than precarious to postulate sources of which nothing is known.3What many mistake as the dependence of John upon noncanonical apocalyptic writings is their common allusion to events from the Old Testament:
The general nature of the Revelation has been described as both apocalyptic and prophetic. Jewish apocalyptic literature can be seen in Isaiah Isa. 24:1-Isa. 27:1, Ezekiel Eze. 38:1-Eze. 39:1, Daniel Dan. 7:1-Dan. 12:1, and Zechariah Zec. 9:1-Zec. 14:1. Similar elements appear in the apocryphal books of Enoch, Baruch, Fourth Ezra, the Ascension of Isaiah, and the Apocalypse of Zephaniah. But none of these are quoted in the Revelation, which draws most of its symbolic imagery from the canonical Old Testament books. [emphasis added]4