Rahamin Elazar's family trekked hundreds of miles through African plain and scrounged for scraps in disease-ridden Sudanese refugee camps in the fulfillment of a lifelong dream -- to settle in Israel.

But when they arrived in the Jewish state, Israeli officials had a surprise for them. As Falashas, or members of Ethiopia's Jewish community, the Elazars were judged as not being full Jews. They would have to undergo conversion according to Israeli standards.

Elazar recalls that as being the toughest part of their resettlement in Israel. "People died for their Judaism," said Elazar, head of the Public Council for Ethiopian Jews. "And now when we get to Israel, we're told we're not really Jews."

Despite the misgivings, thousands of Ethiopian Jews -- who began arriving in Israel in about 1972 -- complied with the Israeli demand that they undergo conversion. But in recent months, as the rate of arrivals from Ethiopia increased, the new Jewish immigrants have refused to participate in the ceremony.

For Israel's 12,000 Ethiopian immigrants, the refusal marks the first organized protest that threatens to split the community's religious leaders from its younger members. But for the chief rabbinate, the Ethiopian move threatens the recognition and acceptance of the community by Israel and world Jewry.

Most lay Jews are unaware of the paradox of an ancient devout Jewish community whose religious identity remains in doubt. Rabbinical scholars throughout the last millenium knew of the Ethiopian Jews, regarded as originating from the ancient Israelite tribe of Dan.

Since the 17th century, the Ethiopian Jewish community has undergone changes that now cast doubts over their religious identity. First, the Ethiopian Jews, according to historians and rabbinical scholars, married into the surrounding Abyssinian community. Jewish law determines the faith of an individual through that of the mother.

In addition, the isolation of the Ethiopian Jewish community led to the adoption of many customs that violated Jewish law, including breaches that affected the religious legitimacy of a family.

For example, Ethiopian Jewish men -- borrowing a custom from their Moslem neighbors -- would divorce their wives by an oral declaration. In contrast, Jewish law specifies that divorce must be in writing and handed over by the husband to his wife. Any other method would not free the woman for remarriage.

Israeli rabbinical leaders assert that the entire Ethiopian Jewish community might be illegitimate and thus unable to marry outside their community -- given the centuries of oral divorce. As a result, the Israeli chief rabbinate was faced with a community whose members may be regarded as either illegitimate Jews or not Jewish at all.

The chief rabbinate preferred to consider the Ethiopians as not at all Jewish. Then, they would undergo conversion and become fully Jewish without any question to their legitimacy that arose from their methods of divorce.

Yedidya Atlas, spokesman for Ashkenazic Chief Rabbi Avraham Shapira, says the process of conversion for Ethiopian Jews is symbolic.

But many Ethiopian Jews find the conversion shameful. In the last few months, young Ethiopians have rebelled against the counsel of their elderly religious leaders and refused to undergo conversion. They have also persuaded all new Ethiopian arrivals to follow suit.

Israeli officials say tension has risen to the point where the head of the Ethiopian community, Rabbi Yosef Adani, hired bodyguards to protect him against younger Ethiopian activists who had threatened attack. Another religious leader was already reported to have been beaten by the activists.

Elazar of the Ethiopian council says the Israeli-educated Rabbi Adani does not represent the interests of the immigrants. "The problem is that he doesn't understand that he should not forget that he's a Jew from Ethiopia -- for good or for bad," Mr. Elazar said.

Chaim Aharon, head of the immigrant and absorption department of the Jewish Agency, said, however, that many of the newly arrived Ethiopians are Marxist-educated and resent their community being headed by a religious figure.

Leftist and anticlerical politicians in Israel have sided with the refusal of the Ethiopians to convert. But the most prominent supporter of this refusal is former Sephardic Chief Rabbi Ovadiah Yosef, who drafted the current policy of requiring a symbolic conversion.

Rabbi Yosef says Ethiopian Jews were always fully Jewish. But to ally fears by more hardline religious figures, the chief rabbis agreed to the symbolic conversion. Ten years ago, Rabbi Yosef says, this policy could win acceptance among the hundreds of Ethiopians who arrived annually to Israel.

"Now when so many are coming and there is such anger against the process of conversion that is so strict, we can concede on this," Rabbi Yosef told rabbinical scholars.