The Book of Jasher: a lost ancient book of the Bible, or a medieval forgery?

In the Bible, there is a reference to the book of Jasher:

So the sun stood still, And the moon stopped, Till the people had revenge Upon their enemies. Is this not written in the Book of Jasher? So the sun stood still in the midst of heaven, and did not hasten to go down for about a whole day (Josh. 10:13) 

and he told them to teach the children of Judah the Song of the Bow; indeed it is written in the Book of Jasher (2 Sam. 1:18)

This work is assumed as lost by most scholars.  But in the visions of Emanuel Swedenborg, he saw that this work of scripture was still extant.  The book of Jasher covers the same period of time in the books of Moses, from Adam to entry into the land of Canaan. As Swedenborg recorded the spiritual meaning of Genesis and Exodus in his work Heavenly Arcana (Arcana Coelestia, or "Heavenly Secrets"), I decided to include a Hebrew work claiming to be the book of Jasher at the end when I published all the works of Emanuel Swedenborg, The Divine Revelation of the New Jerusalem and The Divine Revelation of the New Jerusalem: Expanded Edition. However in the preface, I warned while it contains portions of the original, there are late additions by Jewish writers, who probably assumed it was a late midrash.

I came across this website Sefer haYashar – The Book of Jasher – Book of the Upright, which calls the Hebrew work Sefer haYashar an outright late medieval forgery.  The main arguments that this is a late forgery are the following:

1. The text appeared in the 17th century (possibly earlier in 1552) in Italy, and there is no evidence it existed before that time.
2. It shares stories also found in the Jewish Talmud and the Targums.
3. It contains possible additions from cabbalistic literature (ca. 13th century A.D.).
4. The geneaology of Noah contains references to the Franks and Lombards who appeared after the fall of the Roman Empire, probably borrowed from Josippon, a rabbinic work of the 10th century A.D.

All of this I knew when I decided to include it in the Divine Revelation of the New Jerusalem.  So why did I include it?  It is known that right before the first century A.D. some of the scriptures began to be corrupted - thus we find late additions in some works of the Bible as found in the Septuagint. So just because there are similar stories in the Jewish Talmud and Targums proves nothing. Actually it can work as evidence in favor: just where were these Jewish rabbis drawing upon for all of these traditions?  And before the discovery of the Dead Sea Scrolls, the oldest Hebrew text we had of the Bible dated to the 10th century A.D.  As for the other points, those could be later additions.

The reason why I included the book of Jasher is that some of this text is very, very ancient.  In fact, it can be proven that there is no way this work was composed in its entirety during the medieval era.  I discuss some of the points in detail in my earlier blog entry on the book of Jasher.  As it was seen in the visions of Swedenborg, it is evidence that these visions were not a product of the imagination. Separate from this, Swedenborg was able to see certain things clairvoyantly, one was confirmed by Immanuel Kant. Evidence that the book of Jasher is quite old are the following pieces of evidence:

1.  It mentions a rare astronomical alignment - a grand conjunction - for the birth of Abraham in 1953 B.C.  This could not have been known by a medieval forger.  For a more detailed analysis on this, see the blog entry on the astronomy during the birth of Abraham.
2.  Embedded in the chronology of the ancient patriarchs before the Flood there is some very detailed (and hidden) astronomical information.  One concerns a Venus transit that occurred in the year 3214 B.C. and another in 2971 B.C., and there is an implicit reference to the 243 years which separated these Venus transits in the book of Jasher (it is periodic, and always 243 years).  The explanation for this is a bit detailed, see the blog entry on the ancient astronomy of the Bible.  Last time we had a Venus transit was in 2012. Again, this could not have been known by a medieval forger.
3. In the story of Nimrod there is a reference to a Sumerian god name, which was not known until cuneiform tablets were recovered by archaeologists in the 19th century, and
4. The Apostle Paul mentions Jannes and Jambres as the names of the two magicians who opposed Moses. This is not in the Bible, but is present in the book of Jasher. This however is also mentioned in Jewish traditions.

However, there is more.  The book of Jasher contains some detailed information concerning Abraham and the king Nimrod of Babylon.  These stories are repeated by Josephus, a first century Jewish historian.  According to the Hebrew preface, the work was recovered from the destruction of the Jewish temple in 70 A.D., after which it made its way to Spain.

I have been reading an ancient Jewish work, the Book of Jubilees, written in the 2nd century B.C.  I had this work in my library, but then I discovered that more than any other work copies of this were discovered among the Dead Sea Scrolls.  Its a Jewish rework of Genesis and Exodus, which seeks to put an additional calendar and a 50 year cycle on all events recorded in scripture.  Unlike Jasher, we can see many pieces of evidence that the work of Jubilees is a work of the second century B.C., adding onto the stories of scripture, embellishing it with some very late Jewish traditions. In reading this, I found some notes by the translator on the book of Jasher, which he used to compare with the book of Jubilees.  I want to cover a few of these in detail, before people jump to the conclusion that Sefer haYashar is a later medieval forgery.

First off, we can see the book of Jubilees following the book of Enoch in declaring that before the flood, angelic like beings - (some say extraterrestrials), mated with the women and produced giants. It has got to be one of the strangest Jewish stories added onto scripture some time between the Old and the New Testaments.  Here is what the book of Jubilees states:

...and he called his name Jared; for in his days the angels of the Lord descended on the earth, those who are named the Watchers, that they should instruct the children of men, and that they should do judgment and uprightness on the earth (Jubilees 4:15)

This is based on the following scripture in Genesis:

There were giants on the earth in those days, and also afterward, when the sons of God came in to the daughters of men and they bore children to them. Those were the mighty men who were of old, men of renown. (Gen. 6:4)

This interpretation - that angels made a descent in ancient times and intermingled with women to produce giants - was very popular in the first century A.D.  In that time, or in the second century A.D., Jewish scholars protested against this interpretation.  Rabbi ben Jochai "cursed any one who translated Gen. vi. 2 by the phrase "sons of God," and not "sons of the judges"".  Why would the Jews indicate that not only is it a misinterpretation, but a mistranslation?  Here is the same passage from the book of Jasher:

And their judges and rulers went to the daughters of men and took their wives by force from their husbands according to their choice, and the sons of men in those days took from the cattle of the earth, the beasts of the field and the fowls of the air, and taught the mixture of animals of one species with the other (Jasher 4:18)

While this offers a very interesting story with no end to the amount of speculation at to what it means (giants from another planet with heavier gravity, genetic engineering), Jasher states it was the judges and rulers of men, not angels who descended from heaven. This was an issue of the first and second centuries A.D. Why would a medieval forger again bring up this very ancient controversy?

Another interesting point about the book of Jubilees is that at times it does not follow the Masoretic Hebrew text, but an alternate Hebrew text which was also used by the translators of the Septuagint.  In an alternate geneaology, after the Flood Arphaxad gives birth to one named Cainan - whereas the Masoretic text does not have this, and skips to one named Salah.  And here is what is said concerning Cainan in the book of Jubilees:

Arpachshad took to himself a wife and her name was Rasu'eja, the daughter of Susan, the daughter of Elam, and she bare him a son in the third year in this week, and he called his name Kainam. And the son grew, and his father taught him writing, and he went to seek for himself a place where he might seize for himself a city. And he found a writing which former (generations) had carved on the rock, and he read what was thereon, and he transcribed it and sinned owing to it; for it contained the teaching of the Watchers in accordance with which they used to observe the omens of the sun and moon and stars in all the signs of heaven. And he wrote it down and said nothing regarding it; for he was afraid to speak to Noah about it lest he should be angry with him on account of it. (Jubilees 8:1-5)

In the commentary, this extra generation is added in order to make 22 generations from Adam to Jacob instead of 21, as there are 22 books in the Hebrew Bible.  This extra generation was then copied into the Septuagint.  The story also contains an explanation as to "why" it may not be present in the Masoretic text.  But where did this story come from? Josephus describes a similar story for the sons of Seth before the Flood.  And where did he get that story?  It comes from Jasher, concerning Cainan, the son of Enosh the son of Seth, not Arphaxad:

And Cainan grew up and he was forty years old, and he became wise and had knowledge and skill in all wisdom, and he reigned over all the sons of men, and he led the sons of men to wisdom and knowledge; for Cainan was a very wise man and had understanding in all wisdom, and with his wisdom he ruled over spirits and demons;And Cainan knew by his wisdom that God would destroy the sons of men for having sinned upon earth, and that the Lord would in the latter days bring upon them the waters of the flood.And in those days Cainan wrote upon tablets of stone, what was to take place in time to come, and he put them in his treasures. (Jasher 2:11-13)

The book of Jasher contains the older, more simpler story, which got embellished and misplaced in the book of Jubilees.

And now, there is this other interesting example where the book of Jasher may be a source of early Jewish tradition.  Before the flood, after Enosh was born, Genesis states this:

Then men began to call on the name of the LORD. (Gen. 4:26)

However Jubilees has this:

He [Enosh] began to call on the name of the LORD on the earth (Jubilees 4:12)

Jubilees here agrees with the Septuagint and the Syriac in this verse.  In the time of Jerome, Jewish scholars stated that this refers to the rise of idolatry. This interpretation can be traced back to as early as the first century A.D., for it is found in the Targum Onkelos of that time.  So where does this come from?  From Jasher, where it has the following expanded story:

And it was in the days of Enosh that the sons of men continued to rebel and transgress against God, to increase the anger of the Lord against the sons of men.And the sons of men went and they served other gods, and they forgot the Lord who had created them in the earth: and in those days the sons of men made images of brass and iron, wood and stone, and they bowed down and served them.And every man made his god and they bowed down to them, and the sons of men forsook the Lord all the days of Enosh and his children (Jasher 2:3-5)

So these are minor pieces of evidence, and there is more I can gather but there is no need: the clincher is the astronomical information contained in this work.  The evidence shows, despite some late additions, that this manuscript does indeed contain the ancient lost work of the book of Jasher.