Seventeen percent of self declared, religious, American Jews, say they were raised in another religion. Six percent say they were raised in non-religious, non-Jewish homes, 4 percent were raised as mainline Protestant, 3 percent as Catholic, 2 percent as Evangelical and 2 percent in mixed religion homes or as non-Christians, according to a Pew Research Center 2014 U.S. Religious Landscape Study of 35,071 American adults (847 Jewish by religion).
This means that almost a million of today’s Jews in America were not born Jewish. The efforts of UltraOrthodox Rabbis in Israel and America to push these Jews outside the Jewish People is a Hillul HaShem, which will split apart the Jewish People both in the diaspora and in Israel.
Jewish population studies from previous decades had indicated that almost ten percent of the Jewish community had not grown up in a Jewish home, so the rise in converts from one in ten, to one in six, was surprising in a very positive way.
Based on previous studies of those who were not raised Jewish but now self identify as Jewish; most went through a formal conversion ceremony (almost all Reform or Conservative), but at least 20-30 percent informally became Jewish by living for years as part of an identified and affiliated Jewish family.
The numbers of religious Jews in the survey (847) was to small to find out how many of those non-Jews who now call themselves religious Jews, had a Jewish parent or grandparent, but perhaps ten to twenty percent do. Most converts to Judaism do not know of any Jewish ancestry, but tens of thousands of them do have Jewish ancestors from three to seven generations back.
According to Kabbalah, the souls of self conscious moral creatures like human beings can reincarnate; but they reincarnate only when they have not fulfilled the purpose of their creation.
Since Judaism is an optimistic religion, most Kabbalists teach that most people can accomplish their life’s purpose in one or two lifetimes. A few souls may take 3-5 lifetimes or more. The bright souls of great religious figures like Moses or Miriam can turn into dozens of sparks that can reincarnate several times.
The tragic souls of Jews whose children have been cut off from the Jewish people, either through persecution or forced conversion to another religion, will reincarnate as one of their own, no longer Jewish, descendants. These descendant souls will seek to return to the Jewish people.
A majority of people who end up converting (or reverting) to Judaism and the Jewish people have Jewish souls from one of their own ancestors. Thus, the Jewish mystical tradition (see Sefer HaPliah), claims that the souls of most converts to Judaism are the reincarnated souls of Jews in previous generations that were cut off from the Jewish people.
Through conversion to Judaism they are coming home. Sometimes these souls are descendants of Jews who were part of whole communities that were cut off, like the Marranos or European Jews in Eastern Europe during the Holocaust and then the decades of Communist oppression.
Other times they are descendants of individual Jews who married out and did not raise their children as faithful Jews. This category applies to the majority of converts to Judaism in North and South America.