In essence, it is an easy chance for the Jews to prove that the Quran is false - that it is not a divine revelation. All they have to do is organize themselves, treat the Muslims nicely for a few years and then say, "Now what does your holy book say about who are your best friends in the world - the Jews or the Christians? Look what we Jews have done for you!"  That is all they have to do to disprove the Quran's authenticity, yet they have not done it in 1400 years. But, as always, the offer still stands open!

Standing Offer by God