Since the 20th century, Buddhism and Judaism have become associated due to the common religious overlap in Jewish Buddhists. Somewhere between 16.5 to 30% of Buddhists in the US have a Jewish background or maintain a relationship to Judaism, in contrast to the 2 to 3% of the US population that is ethnically or religiously Jewish.
According to the Ten Commandments and halakha (classical Jewish law), it is forbidden for Jews to worship any deity other than the God of Israel—specifically by bowing or offering incense, sacrifices, or poured libations, in Exodus 20:4-6. It is likewise commonly understood as forbidden to join or serve in another religion as doing so would render the participant an apostate or idol worshipper. On the surface, this makes some Jews and Buddhists skeptical of people who claim to be both, especially if they are practicing both religions simultaneously.
However, since many Buddhists do not consider the Buddha to have been divine in the same sense traditional Jewish theology and the Hebrew Bible understand, Jewish Buddhists do not consider Buddhist practice to be worship despite some practices, such as incense and food offerings made to a statue of the Buddha, as well as prostration and bowing to statues of the Buddha, having an outwardly worship-like appearance. Some Jews cite that the Buddha himself would not eant to be prayed to, as is well known in scripture, making it clear the intention is not "praying to" Buddha. Some also do not consider the bow to be prayer simply because they are not doing it with the intention of prayer. In addition, many Buddhists do not worship the Buddha; instead, they "revere" and "express gratitude" for the Buddha's (and all buddhas') accomplishment of reaching Nirvana and compassionate teaching, respectively. Buddhists honor the Buddha for discovering and teaching the Dharma, enabling others to be freed from suffering and thus attain Nirvana. While the worry about what practice is permitted and what is not remains, with Orthodox leaning Jews being more likely to disapprove, even some Orthodox rabbis admit to being unsure if it is permitted or not, though they usually do not wish to be named.
It is also worth noting that early Buddhism likely did not use statues. Additionally, some Japanese Buddhists (especially in the Nichiren school) prefer to use a special form of calligraphy (gohonzon) on their altars instead of a statue to represent their reverence for Buddha and bodhisattvas, though both may be used simultaneously. This reverence has a parallel in Jewish reference for scripture and its quotations. Items that have certain things written in them (usually a sacred name of God) need to be buried when damaged beyond use or repair, which includes both Torah scrolls (which are handwritten by trained calligraphers) and prayer books (which are mass printed), among other items. Scriptural quotations are also sometimes made into calligraphy that is used during prayer to focus one's intentions, such as shivitis or mizrachs.
Some Jewish Buddhists do feel uncomfortable with the use of statues in prayer and meditation spaces and may prefer not to have them present. Some teachers may accomadate this while also demonstrating that the statue itself is unimportant to the tradition. Others will pre-emptively remove statues or have them not be present at all. Interestingly, some Jewish meditation groups will hold their sessions in the same room as a Torah ark, though close examination of if the Torah scroll is being used a substitute for traditional Buddhist imagery (such as statues) has not been done.
Some Jews find that Buddhist practices like tantra, mindfulness, and meditation have inspired them to be a better Jew, encouraging them to pray more often, read scripture more frequently, and to keep shomer Shabbat as a form of weekly retreat for meditation and study. Others find that their dual identity is a mosaic, or a tangled set of vines, and that it may be "unfair" to each religion, or that it makes them deficient in some way to both, but that they are at peace with it and don't care much. Some who are (or were) JewBus come to the conclusion you can't be both, even as they admit one of the traditions still influences them. Others believe dual religious identity is possible, or even easy. Some American Buddhist centers specifically encourage people to reconcile with their birth religion, which helps some Jews feel strongly about their Jewish identity while continuing Buddhist practice.
Dually religious Jewish Buddhists tend to be lay people in Buddhist terms, but a large number of them are rabbis or cantors. They tend to attend synagogue or a minyan regularly, and have limited affiliation with Buddhism. They tend to engage with Buddhism through books and private meditation or occasional retreats, but generally lack offical ties to Buddhist organizations. They tend to view themselves as spiritual, be socially and politically liberal, and are slightly more likely to be women, though this is based on a small sample size. They also do not always identify as Buddhist, with many saying they are meditators. Sylvia Boorstein discusses a trepidation she felt on this front, having described herself as a "meditation teacher" for some time before admitting she was a Buddhist to herself. For Boorstein, part of her hesitation was a fear of judgement and rejection from other Jews. In order to navigate "acceptable" cultural blending and avoid the internal and external accusation of avodah zarah, many syncretic Jews will adopt Buddhist practices (primarily meditation), but avoid things they classify as belief (taking vows, celebrating holidays, self identification, and participating in or accepting mythological/cosmological ideas). However, they almost never take part in communal activities with Buddhists as practice, restricting these to once a year events. Some of them were, or almost were, ordained in Buddhism. These people do not necessarily disavow Buddhism, saying things such as "If it [spiritual truth] was here [Buddhism], it must be there [Judaism] as well, even if it’s a little more mucked up and harder to find, and that I would consciously make the move not away from Buddhism per se but back into Judaism".
Many Jewish Buddhists in the US feel little to no attachment to Buddhism as it is practiced in Asia and practice specifically Americanized forms of Buddhism. Most are not multigenerational Buddhists (though this may change as time passes) and came to engage with Buddhist traditions on their own as adults. While interactions between Jews and Buddhists have been marked by uneven power relations and white Jews remaking Buddhism to suit their purposes and to increase it's compatability with American society (often at the expense of Asian perspectives) the conflict in an American context lacks the violence from early Buddhist-Christian interactions (wherein white Christians victimized Buddhists via colonization and missionary efforts).
The theories for why Jews are attracted to Buddhism include:
Buddhists have never historically persecuted Jews. Many Jews have faced a community wide, recent trauma that has forced them to contemplate suffering, and Buddhism has tools to comprehend this. Modern Jews are more secularized than Christians in the US, and are positioned as outsiders in a way that makes them more willing to embrace ideas seen as foreign. Both religions have well developed scholastic and scriptural traditions. The way Jews think about God may actually be uniquely suited, out of all the major monotheistic religions, to fit inside nontheist Buddhism. Buddhism limits its theological demands on followers and does not emphasize choosenness, a principle more and more Jews are frustrated by. Instead it is universalist. Buddhist and Jewish mystical traditions have noted similarities, but Buddhism makes its mysticism more accessible. Jews occupy a specific social strata that Buddhism often appeals to: the "highly educated upper middle class, intellectuals, artists, and bohemians." Buddhism has "pull factors" that appeal to Jews, such as: being a "body-based practice that lends itself to direct experience"; Buddhist practices have been consciously reworded and presented anew for Western audiences, increasing their appeal; an appreciation for mindfulness in an age of electronics; and the particulars of the Buddhist approach to ending war, poverty, discrimination, environmental destruction, and substance abuse.
History 17th and 18th century Some scholars believe Buddhism and particularly Buddhist shamanism may have had a role in the early development of the Eastern European Hasidic tradition and its use of ritual techniques like trance and hypnosis. This is potentially possible due to the influence of Kalmyks in particular, a few of which converted to Judaism. Some Jews of Kalmyk ancestry claim they are descendants of Khazars, who after the destruction of the Khazarian kingdom were assimilated into Vajrayana Buddhism but retained a few Jewish customs. Their family lore indicates they likely first interacted with Jews in Poland after this while commissioned to protect civilians. Later, some of them settled in Belarus and married Jewish women after converting to Judaism. This community likely had a significant overlap with Cossack Subbotniks/Judaizers. Many of these Judaized Cossacks protected other Jews from violence during early 20th century conflicts, such as the Russian civil war. Very few of them exist in Russia today, as many were deported by Stalin and some left for Palestine before the founding of Israel as a modern state. Supposedly, a village exists in eastern Siberia of people descended from Judaized Cossacks who were celebrating Passover as recently as 1986, though they hide their religion from outsiders. It is worth noting this family history is oral lore which is difficult to verify, and discussions of the Khazars are often fraught with conspiracy and antisemitic rhetoric.Mustafa, Raza Ul; Japkowicz, Nathalie (6 February 2024), Monitoring the evolution of antisemitic discourse on extremist social media using BERT, arXiv:2403.05548
19th century The first American Jew known to have converted to Buddhism in the US was Charles T. Strauss, who converted to Theravada Buddhism in 1893 after the World’s Parliament of Religions in Chicago. Prior to this he had studied western texts on Buddhism for several years and attended the conference specifically to learn more about Buddhism. Strauss was born in Switzerland and had immigrated to the US at age 18 in 1870. While this event is the most notable 19th century interaction between Jews and Buddhists, it is not the only interaction. Newspaper articles from the time show many Americans, including many Jews, were interested in Judaism during this time. Strauss attested that he never identified as religiously Jewish and had only occasionally been to synagogue before his conversion to Buddhism. He was brought up in a milieu of liberal (probably Reform) Judaism, which emphasized social justice, rationalism, and universality.
Strauss studied Pali, contributed to efforts to revive Buddhist institutions in Asia after the damage done by colonialism, and helped establish the first Buddhist community in Western Europe in Leipzig. As a wealthy man he was able to travel between Germany and Sri Lanka, aiding his efforts. During the beginning of World War 1, he fled to Switzerland and lived there until he died. During this time he wrote The Buddha and His Doctrine, a book about his Buddhist practice and his belief in its compatability with rationalism, social justice, individualism and religious liberalism. He mainly focused on his Theravada tradition, portraying it as "original genuine Buddhism" (a biased and Orientalist view common among westerners at the time). Part of his motive in writing was to defend Buddhism against the allegations that it was nihilistic and atheistic.