[SauronOfMordor]

Doesn't Israel have some definition of jewishness?

"Jewishness" is matrilinial -- ie you are Jewish if your mother is Jewish. Your mother is Jewish if HER mother was Jewish, and so on. So you can be Jewish under the Israeli "Law of Return", even if you and your parents have never been practicing Jews, as long as your lineage is correct

[Edmund Burke]

How did Sammy Davis fit in to this definition? Did he have a "right of return"?

[skraeling]

> "Jewishness" is matrilinial -- ie you are Jewish if your mother is Jewish.

That is only a manmade rule, created to serve a political need. Jesus lineage is patrilineal (See Matthew 1.)