Do you have any ideas about the origins of the Star of David?
I have heard that 'The Six Pointed Star' by O. J. Graham is an informative book which views the symbol as occult, but I have not yet read this book.
In Byzantine times, Christians venerated a ring with the Seal of Solomon, which is supposedly the same thing.
Could you mention more details or the source of this information?
isn't it questionable whether the Jews as a national group will rule the world in the apocalypse?
To answer your question precisely, I would have to say I do not know. Nor do I specifically recall reading any Christian prophecy to the effect that Jews as a national group will rule the world.
I have read more than one prophecy (such as Saint Methodius of Patara) that specifically states that the antichrist will be a Jew of the tribe of Dan who "will be born in the town of Chorazaim, nourished in Bethsaida, and reign in Capernaum" which are the three towns that our Lord Jesus curses in the Gospel of Luke.
However, I do believe what I have read in the life of Saint Andrew the Fool for Christ that after the city of Constantinople is physically submerged in the sea bringing gentile power to an end the Jews as a national group will be regathered to the land of Israel from across the world as in the days when they fled Egypt. It has been a while since I read this prophecy, but I do not specifically recall mention that the Jews as a nation will rule the world. I'll have to take a look at it.
(The Andreas Salos Apocalypse
translated by Lennart Ryden, Dumbarton Oaks Papers Volume #28, 1974)
This is probably the best and most detailed Byzantine prophecy I have come across (although Saint Methodius is also worth mentioning.)
I photocopied this in both Greek and English translation a few years ago at a well stocked university library which has old annual volumes issued by the Dumbarton Oaks Centre for Byzantine Studies, but the only place I found this on the internet is JSTOR which does indicate it permits a free ten day registration for three downloads. Otherwise, most university libraries subscribe to JSTOR meaning someone can simply walk in & bring it up on a computer and print it out or save it to their email. It is about 20 to 25 pages total including the intro and both translations of about ten pages each. http://www.jstor.org/discover/10.2307/1291359?uid=3739600&uid=2129&uid=2&uid=70&uid=4&uid=3739256&sid=21102559568187