It is far easier to determine cross-pollination in the realm of nature than in the world of religion. Scientists spend endless hours watching the process in the field and analyzing the evidence in laboratories. But how can theologians and other scholars ever be fully confident that the spiritual thinking of one group of people influenced the religious development of another? This is particularly problematic if the interpreters of history are blinded by their own religious persuasions and documentation is not only minimal but, in some cases, unreliable.
Nevertheless, in one way or another and often unconsciously, all religions have drawn on beliefs and practices of other traditions they have encountered. Sometimes the blending is the result of marriage between a woman of one spiritual community and a man of another. At other times it is the consequence of traders of different persuasions coming into contact, even settling down outside their own society. In addition, converts to one tradition carry with them ideas, beliefs, and stories from their own heritage. Close proximity of diverse neighbors can also lead to sharing practices. For example, although Jews do not have a history of asceticism, in medieval Germany there were pious Jews who incorporated severe austerities after having observed them among Christians. And some Jews living in the medieval Islamic societies of the Iberian Peninsula and North Africa studied with Sufi masters. The reverse is true as well: the development of both Christianity and Islam reflects borrowings from Judaism.
Whenever history has brought different peoples to live together, religions have modified each other, sometimes to their mutual benefit and sometimes not. In Latin America, Roman Catholicism was grafted onto indigenous spiritual systems. In China, where Buddhism commingled with Taoism and Confucianism, it took on a different form than in Sri Lanka (Ceylon) or Myanmar (Burma).
Some of what happened many centuries ago is traceable, but much of it has disappeared in the mists of time. However, today, when it is clear that no religion is an island, as Rabbi Abraham Joshua Heschel (1907-1972) pointed out, there is the opportunity to experience a great range of religious life. We can consciously witness how interfaith exchanges take place and document them. One such active contemporary exchange is between Buddhism and Judaism. Since the final decades of the 20th century, an unprecedented and disproportionate number of Jews have been drawn to practice in the different schools of Buddhism-Therava - da, Maha-ya- na, and Vajraya-na. This phenomenon poses a curious question: Is it an anomaly, or has a Jewish-Buddhist dialogue occurred before? While it is difficult to determine what actually transpired in the distant past, several writers suggest that Buddhists and Jews have known each other for at least 2 millennia and possibly much longer. Others are convinced that there was no early exchange or direct impact. Those who subscribe to linkages between the two groups in the ancient world point out that along with merchants, there were also ambassadors, emissaries, and missionaries who traveled the trade routes connecting India with regions to the west. For example, in the third century B.C.E., King Ashoka's deputy to Alexandria may have influenced the author of Ecclesiastes. One scholar notes that Jews were a trading connection between Christian Europe and Hindu- Buddhist India and Jewish settlements appeared in India in the first century. And the "silk road" between the Chinese and Roman empires passed through the Negev Desert of Israel.
There are references to India in early Jewish historical writings as well as in the Talmud, which includes some Sanskrit words. By the early medieval era, Jewish merchants made a whole body of Buddhist literature (the Ja-taka tales) available to the Western world. Interestingly, one story in particular parallels the judgment tale of King Solomon in Kings 3:16-28. Thereafter, little to nothing is heard about a connection between Jews and Buddhists for many centuries.
In America, there was no public conversation about Buddhism until the mid- to late 1800s, and those who engaged in it were generally New England men of British and Protestant heritage. However, it was a Swiss-born Jewish businessman from New York City, Charles T. Strauss, who was both the first Jew and first westerner to publicly embrace the Buddha's teaching on American soil. At the World's Parliament of Religions of 1893 in Chicago, he performed the ceremony of taking refuge in the Buddha in front of an overflow crowd and remained devoted until his death. Like the trade routes that opened relations between the Near East and Far East in ancient times, modern transportation and media have opened relations between Western Jews and Asian Buddhists. Austrianborn Israeli philosopher Martin Buber (1878-1965) received visits from Japanese ro-shi (Zen master) Nyogen Senzaki (1876-1958) in Jerusalem and from Buddhist scholars D. T. Suzuki (1870-1966) and Masao Abe in New York. Israeli Prime Minister David Ben Gurion (1886-1973) discussed ties between Jews and Buddhists with Burmese Prime Minister U Nu (1907- 1995) on TV in 1959.
During the "Zen boom" of the 1950s, beat poet Allen Ginsberg (1926-1997) proclaimed himself a "Buddhist Jew." Interest in Buddhism grew in the 1960s after some westerners who had practiced in Japanese temples in the 1950s returned and wrote about it. Foremost among them was Philip Kapleau (1912-2004), who became the first westerner ordained as ro-shi. By the 1970s an estimated 50% of Zen people in San Francisco and 33% in Los Angeles were Jews, though the total Jewish population in the United States is estimated around 2%.