Trying to counteract the loss of membership and vitality in one of Judaism's principal groups, the Conservative movement yesterday launched what its leaders said will be an aggressive effort to convert to Judaism the gentile spouses and children of Jews who have married outside the faith.
The move is a break with a centuries-old Jewish tradition of shunning conversion efforts, an aversion traceable to the hostility that such efforts generated in countries with Christian or Muslim majorities. Even in the United States, Jews did not consider the idea of converting gentiles until the late 20th century.
The new policy is needed to preserve Jewish families in the face of high rates of intermarriage and assimilation among American Jews, said Rabbi Jerome M. Epstein, chief executive officer of the United Synagogue of Conservative Judaism, a union of the 760 Conservative synagogues in the United States and Canada.
''We must begin aggressively to encourage conversions of potential Jews who have chosen a Jewish spouse," Epstein told representatives of the synagogue association's convention at Boston's Park Plaza Hotel. ''And if conversion is initially rejected, we must continue to place it on the agenda."
Conservatives -- who attempt to strike a balance between Orthodox Judaism's stricter adherence to Jewish law and the liberalism of the Reform movement -- once were the largest grouping of Jews in the United States. Since the early 1990s, the movement has fallen behind Reform Judaism in absolute numbers and behind both Reform and Orthodox Judaism in institutional vigor.
The National Jewish Population Survey of 2000, the most recent comprehensive data available, found that among Jews who affiliated with a temple or synagogue, 38 percent were Reform, 33 percent Conservative, and 22 percent Orthodox.
Orthodox Jews have a much higher birth rate than either of the other groups. The Reform movement has been gaining intermarried families in which the Jewish spouse was once Conservative but no longer felt comfortable in a Conservative synagogue after marrying a non-Jew, according to the population data and demographic authorities.
Orthodox Jews maintain the tradition of discouraging conversions, while the Reform movement welcomes non-Jews who wish to convert. It is also fully accepting of intermarried couples, a position the Conservatives are far from adopting.
''We must become the movement that passionately encourages conversion and the raising of Jewish children . . . if we want to create a vibrant Jewish life," Epstein said. He called on clergy and lay leaders to make visits and telephone calls to invite gentiles married to congregants to participate and have their children participate in Jewish life.
Detailed suggestions to member congregations were distributed after Epstein's speech, the keynote address of the convention, which is held every two years. The suggestions proposed making special efforts, including scholarship offers, to encourage unconverted children who have a Jewish parent to participate in Jewish youth organizations and to visit Israel, to encourage and deepen their sense of positive Jewish identity.
In an interview, Epstein estimated that the potential pool of converts numbered ''easily more than 1 million people," based on a Jewish intermarriage rate that for many years has been running at 50 percent or more of all marriages involving Jews. He said the staff of the association of congregations has been preparing a campaign since September to bring the conversion initiative to the congregations after it was presented at the convention.
''We have unveiled it; now we will go to the individual congregations to sell this," Epstein said. ''I think people will be excited by it."
There are about 5.2 million Jews in the United States, according to the 2000 population survey. The Conservative movement says 1.5 million of them are members, but Leonard Saxe, a demographer and professor of social policy at Brandeis University, said the number is more probably 600,000 to 700,000.
Delegates to the convention seemed to generally approve of the initiative's effort to make Conservative congregations more welcoming to non-Jewish spouses and children of Jews and to encourage them to convert. But there was disagreement over whether this issue should be the top item on the Conservative agenda and on whether even a highly successful campaign would dramatically improve the situation of the Conservative movement.
James Lebeau, a longtime Conservative rabbi in Lowell who now is the synagogue association's Israel representative, said the issue of non-Jewish spouses and children ''is one of the most urgent issues facing our movement." He applauded the initiative as an effort to ''strengthen the movement by strengthening families."
Lebeau, like Epstein, stressed statistics that indicated that only 22 percent of children of two Jewish parents marry out of the faith, compared with 74 percent of children with only one Jewish parent.
Others at the convention -- like Rabbi Joel Meyers, executive director of the Conservative Rabbinical Assembly -- said the initiative is worthwhile, but that the real problems of Conservative Judaism are related to its position as a centrist movement between Orthodoxy and Reform.
''What has happened is that the Orthodox have picked up and used some elements of the Conservative approach," particularly by heightening their involvement in social action alongside other faiths, Meyers said, ''and the Reform movement also has taken certain features, especially by returning to elements of traditional religious observance, using more Hebrew, wearing kippahs," the traditional Jewish head covering.
''How the Conservative movement thinks about its mission and identity in the 21st century is the real question," he said.
The conversion initiative ''is important," Meyers said, ''but it is not the essence of what needs to be done." The rabbinical assembly leader said he is not yet ready to put his own proposals forward.
Jonathan Sarna, a Brandeis history professor and a leading chronicler of the American Jewish experience, said in a telephone interview: ''You've got a movement that is in trouble and different people are putting forth different directions" to revive it. ''It is seeking to regain its footing."
Charles A. Radin can be reached at email@example.com.