Jewish identity is a complex issue, akin to the question of “who is a Jew?” It has become even more complicated with aliya from the former Soviet Union countries, with at least 30 percent of these immigrants not being Jewish. Complications also emanate from the West with increased intermarriage, and criteria of acceptance of Jewish status by the various streams of Judaism. A further difficulty is a postmodern phenomenon of “I wish it, so I am.”In the context of Jewish identity this may manifest itself in one of two ways. 1) I have Jewish DNA from a distant ancestor, with whom I feel a great affinity – so I am Jewish. 2) I love things Jewish, so I am Jewish.The latter sentiment may be fueled by a popular Jewish media phenomenon of digging up some Jewish roots of famous persons. It may also be fueled by such stars as Madonna who promote Kabbalah, and attracts those who want to be Jewish Kabbalists. There is also the issue of young people serving in the IDF defending Israel and the Jewish people, and yet who are halachically not Jewish.There are, however, organizations that are facilitating their conversion through the army.The question of who is a Jew became a big issue in Israel in 1958 when prime minister David Ben-Gurion asked 50 intellectuals the question. More specifically the inquiry focused on the issue of whether a girl born of a Jewish father could be accorded the right of return to Israel. One of those intellectuals was my grandfather, who was then the Hacham of the Sephardi community of Holland. He had also been the first chief Jewish chaplain of the Dutch armed forces.He gave the classical answer, as did other Orthodox respondents including the Lubavitcher Rebbe: a Jew is one born of a Jewish mother or one who converted according to halacha under a properly constituted Orthodox Beit Din. The Israeli government chose rather to define a Jew as: “Anyone who chooses in good faith to call himself a Jew [and] who does not profess any other religion.” This definition was opposed by Orthodox factions. The National Religious Party threatened to withdraw from Israel’s coalition government. This forced the prime minister to cancel directives issued by the interior minister concerning registration of children of mixed marriages.However the attorney-general of the day confirmed the designation, which stated: “the fact that according to the Law of Moses and Israel a man is not accepted as a Jew does not prevent that man from being considered as a Jew so far as the laws of the state are concerned.”This was not the first time a definition of who is a Jew was formulated that contradicted halacha. The issue also arose in 1806 when Napoleon’s imperial commissioners sent a question to the Assembly of Jewish Notables in Paris: “May a Jewess marry a Christian or a Christian woman a Jew?” The assembly answered that according to the view of the Bible only marriages with Canaanite nations were forbidden.The assembly pointed out that intermarriages were allowed because the nations of Europe were not considered idolaters. This answer was opposed by its Orthodox members.Even post-1958, the question of who is a Jew has been revisited several times in Israel. In 1970 the Supreme Court ruled that membership in the Jewish nation was separate from membership in the Jewish faith. Chief Justice Shimon Agranat wrote: “The goals of aliya and the ingathering of the exiles, obligate us to see the term ‘Jew’ as a secular dynamic concept.”The religious parties succeeded in having an amendment placed in the law that “A Jew in religious terms is one whose mother is a Jew.”Today the Reform and other progressive streams of Judaism contend that patrilineal Jewish status is also valid, arguing that originally a Jew who was born of a Jewish father was considered Jewish, although up until 1983 the Reform movement also subscribed to matrilineal Jewish status. Orthodox streams still uphold the halachic definition of Jewish status as one who is born of a Jewish mother or who is converted according to Jewish law. Yet should this definition be understood in strict or lenient terms, and can it be canceled retroactively? Rabbi Haim Amsalem in his book Am Yisrael appears to follow the lenient view of many Sephardi rabbis, including the late Sephardi chief rabbi of Jerusalem Shalom Massass, who contend that after the fact, it is permitted to consider a convert to still be Jewish even if he or she shows little evidence of sincere acceptance the yoke of the mitzvot.Others, for example the former Rosh Beit Din of London, Dayan Chanoch Ehrentrau, have the view that if the convert is not observant, it indicates that he or she had no intention of accepting the yoke of the mitzvot, and therefore one can retroactively cancel a conversion.According to Prof. Jonathan Webber, the Holocaust has also had an influence on the issue of Jewish identity. Some people argue that if Hitler identified someone or their family as Jews, then they are Jews. I met a woman who had experience of Nazi-occupied Europe. Her father was Jewish, but her mother was not. She nevertheless thought of herself as being Jewish and regularly attended Shabbat services, and was active in the community.Eliezer Bar-Raphael suggests it is possible to describe Jewish identity: “Not a single identity, but perhaps as ‘a family of identities.’” There is also the phenomenon of a personalized Jewish identity that has been influenced by an individual’s own narrative, experiences, outlooks and lifestyle.Yet as Bar-Raphael suggests, “despite all the differences, Jews share what Ludwig Wingenstein called ‘family resemblances.’” Jews, he contends, have a shared heritage no matter what differences may exist. Those differences may be matters of status, religious outlooks and even cultural.Yet they share what Bar-Raphael calls “a collective identity,” and at times a common collective narrative and history.Jews from different parts of the world have different attitudes, outlooks and cultures, yet share a common Jewish humanity and heritage.The late Rabbi Immanuel Schochet, while recognizing different Jewish identities, however, holds that the only logical definition of who is a Jew is the religious one. Added to the complexities of Jewish identities are groups around the world who claim some form of Jewish identity. Shimon Matlofsky suggests at least 36 groups claim Jewish identity, including the Samaritans in Israel, the Makuya in Japan, the Lembas in South Africa, and the Jews of Kaifeng in China.The answer to overcoming these complexities and stopping a potential ticking time-bomb may lie in Rabbi Amsalem’s suggestion to have a more pragmatic halachic approach to the question of Jewish status and conversions.Yet it will also need supporting efforts to strengthen real Jewish identity.The writer has been a communal rabbi for the past 30 years,- serving three communities in the UK and Hong Kong. He is also an expert in healthcare, spirituality and multifaith issues, and together with Rabbi Harris Guedalia founded Shaare Ratson, the Spanish and Portuguese Congregation in Israel.