cause their father is satan.  the fact is that the jewish religion rejects christianity & jesus precisely on the premise that it is tainted by hellenism(greek culture), the new testament is after all written in greek and is ripe with greek philosophy. the ethnic origins of jesus or indeed his historicity have always been questioned and have always been irrelevant to his message. rabbinic judaism officially considers his good news(euaggelion) message to be a greek message, rather than a jewish one, regardless of his parentage. think about it this way, is george washington more of an american or more of an english man? his parents were english, on both sides after all and that is confirmed by actual documents. do people call him english/british or american? lastly, jesuss "jewishness" is in itself an oxymoron as rabbinic judaism was created after the destruction of the temple( .ie after jesus was born & martyred) and christianity considers only itself as the legal continuation of temple judaism so even official christian doctrine does not accept the proposition that jesus was jewish in the sense of being a member of the community that are called jews today( .ie followers of rabbinic judaism).
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