JUST inside the entrance to Moscow's Central Synagogue on Arkhipova Street, an advertisement is posted: ``Hebrew Lessons, telephone 167-50-52.'' Not long ago, the poster would have been illegal. Learning Hebrew was considered a crime. Police raided private lessons in apartments and locked up the teachers.
Under Mikhail Gorbachev, an organized Jewish community is reviving in the Soviet Union. More and more of the 3 million- plus Soviet Jews are studying Hebrew, learning about Jewish history, celebrating Jewish holidays, and returning to synagogues.
A new Jewish cultural center has opened in Moscow, named after Solomon Mikhoels, a renowned Russian Jewish theater director who was a victim of Stalinist persecutions in 1948.
Relations with Israel are warming. Although there are still no formal diplomatic ties between Moscow and Jerusalem, consular officials have set up offices. Soviet Jews are starting to visit the Jewish state, and Israelis are visiting the communist homeland of many of their grandparents.
``Since the Revolution, there's been no Jewish culture to speak of at all in the Soviet Union,'' says Pina Rabina, a Jewish community leader in Riga. ``Then all of a sudden in the last half a year, we've begun to reconstruct everything that was lost.''
Amidst this reconstruction, the most emotional issue remains emigration. During the 1970s, tens of thousands of Jews left the Soviet Union. During the 1980s, as East-West relations deteriorated, the numbers dwindled. But the Soviets are again issuing large numbers of exit visas. After years of waiting, 19,286 Jews were permitted to leave last year.
For unhappy refuseniks like Emmanuel and Judith Lurie, the improvements haven't helped. They first applied to leave 10 years ago, in January 1979. Mrs. Lurie's mother was able to settle in Israel. Emmanuel and Judith were refused because, like numerous other Jewish scientists, he worked for a short time three decades ago in a classified job at a chemical plant. According to the authorities, he retains knowledge of ``state secrets.''
Mr. Gorbachev recently promised to relax ``secrecy'' laws which deny emigration visas to anyone who worked even decades ago in classified factories. He also promised to ease rules which permit parents to prevent their children from leaving. Potential 'emigr'es must now get the permission of all their immediate family. But Mr. Lurie received another refusal from the authorities in January, and frustrated refuseniks staged a hunger strike in nine cities around the country earlier this month.
Another problem for the refuseniks comes from the American side. Most Jewish 'emigr'es no longer view Israel, with its compulsory military service and Palestinian uprising, as the most attractive new homeland. They instead head for the United States.
American visas used to be granted on request. But the new Soviet openness has made it much harder for Soviet Jews to qualify as refugees under US law. Applicants must demonstrate a ``well-founded fear of persecution.''
In January, the US Immigration and Naturalization Service began issuing its first refusals to Soviet 'emigr'es. Officials at the US Embassy in Moscow say they are overwhelmed with applications. Thousands of Soviet Jews who have left now have become ``waitniks'' stuck in a dreary seaside resort just outside of Rome.
``I've dreamt of leaving the Soviet Union for years,'' says one young Jew considering emigration in Riga. ``Now when I finally can go, I can't get a visa to go to the United States.''
For those Jews who don't want to leave their homes, much hard work remains ahead to rebuild Jewish culture. The process has gone furthest in the Baltic states, where Jewish communities have reorganized under the umbrella of grass-roots Popular Front movements. Elsewhere, there's a strong feeling of improvisation and uncertainty to the Jewish renaissance.
``To set up the first Jewish library, I had to give 250 of my own books,'' says Vladimir Mushinski, head of Jewish Information Center in Moscow. ``There's a lack of trained Hebrew teachers, there's a lack of history teachers, there's still no classroom, no regular lectures.''
Fear also prevents many Jews from cultural activism. Under Soviet law, Jews are considered a ``nationality.'' Their passports are stamped ``Jewish.'' For years, the mark restricted job and educational opportunity.
``My mother is Jewish, my father Russian, so when it came time to decide what nationality to declare for my passport, I chose Russian,'' says one young woman. ``Many Jews do the same thing to avoid problems.''
Thanks to glasnost, Soviet authorities finally have admitted the discrimination against Jews in higher education and promised to end it. But openness also has given space for a strong popular strain of anti-Semitism to resurface. In public meetings, leaders of a Russian nationalist group, Pamyat, blame a ``Jewish conspiracy'' for Russia's problems.
``Comrades, Russian Patriots, how long can we put up with the dirty Jews brazenly penetrating our entire society, especially in profitable places?'' one Pamyat leader reportedly screamed in front of a crowd in Leningrad.
Jews fear that the answers to these questions could result in a new era of pogroms. Many refuseniks say they have received anonymous telephone threats. At the Central Synagogue, an official says, ``people have started referring to me again as `the Yid.'''
``I used to be scared when the police came around the synagogue,'' he adds. ``Now it's gotten so bad that I often call the police to come and protect us.''
No matter the dangers, no matter the difficulties, there is a palpable sense of excitement among ordinary Jews over rediscovering a long-lost identity.
``There used to be two solutions to being Jewish: emigrate or forget about your identity and assimilate,'' says Valeri Colender, another Jewish leader in Riga. ``Now we have a third option - stay and be a Jew in the Soviet Union.''
A meeting of the ``Jewish Booklovers'' shows the hunger for Judaism. Held in a small 13th floor apartment in one of Moscow's nameless housing blocs, it attracts a standing-room-only crowd to hear a talk on Israel from two visitors from Jerusalem. There are all ages, from early teens to grandparents. They ask questions in Russian, in English, and in Hebrew - and listen with intently to the responses.
``A few years ago, before Gorbachev, I would have been scared to come here, scared that someone would see me, tell the people at my work, and ruin my career,'' admits Irna, a schoolteacher attending her first meeting of the ``Booklovers.'' ``When a friend told me about this meeting yesterday, I still was afraid, but then he told me you could learn about Jewish history and philosophy, and meet these guests from Israel. Well, it was just too tempting.''