The current ‘Jewish calendar’ comes from Rabbi Yose ben Halafta and his Seder Olam Rabbah (The Great Order of the World, AD 160). For one thing, there is a 60-year shortfall because the Rabbi was mistaken about Terah... But more seriously, this Rabbi stripped over a century to make the Daniel 9 ‘Seventy Sevens’ prophecy fall on the false messiah Bar Kochba rather than on the true Messiah, Yeshua.
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