MOSCOW, OCT. 15 -- Ira Nudel, now 56, divides her life into two distinct phases -- between her days as the dutiful Russian girl, and the turbulent period of what she calls "my personal revolution" in discovering her Jewish identity.

The first period began when, as a 3-year-old, Nudel moved from the home of her devoutly Jewish grandparents in rural Russia to live in Moscow with her parents. "They forbade me to speak Yiddish," she recalled in an interview at the Moscow apartment of friends shortly before her departure today for Israel. "It was their dream that no one would see a difference between me and a Russian girl. That was the way in the anti-Semitic world of Russia in the 1920s and '30s."

At first, she tried to assimilate, but, inevitably, the first phase brought moments of pain. As a 19-year-old student, she confronted anti-Jewish prejudice for the first time. "Hitler should have finished the job he started," she remembers a Russian classmate saying as he stared at her one day over lunch. "I was crushed," she recalled.

Instead of rebelling openly, she withdrew. "For three years, I entered the classroom when the teacher did and left when the teacher left. I didn't talk to any students at all. How could I forgive that remark?"

Later, she worked quietly as an economic expert at construction sites and shied away from life in the Jewish community. "I didn't go to the synagogue, and I didn't study Hebrew," she said. "Worst of all, I had no Jewish friends."

Nudel's revolution came years later, when a wave of Jewish activism sweeping the Soviet capital in 1970 caught her attention and soon dominated her life. It was an involvement that brought constant harassment by the KGB secret police and a four-year exile to Siberia. It culminated today with her joyous departure from the Soviet Union.

Nudel attributes her second phase to the Soviet authorities having allowed widescale Jewish emigration to Israel for the first time in the early 1970s, inspiring a mass response among Moscow's Jews. "I was among my own, and I was alive," she said.

Lessons in Hebrew and Jewish history soon followed, but most of all the second phase was marked by intense activism. Along with fellow dissidents Josef Begun and Andrei Sakharov, Nudel was in the front lines whenever there was a protest for increased Jewish emigration or against perceived anti-Semitic actions by Soviet authorities.

Diminutive, wiry and bespectacled, Nudel hardly looks the part of the fiery activist. "I had my troubles," she said impishly, "but I must admit it was always I who provoked. It's my way."

Following a demonstration in 1978, she was tried for "hooliganism" and sentenced to four years' exile in a Siberian village. "I was known in town as the enemy," she said. "No one spoke to me at all." The day her exile ended, however, a Christian peasant came to bless her. "Somehow," she said, "that was enough."

In recent months, Nudel has decried the unofficial Soviet organization Pamyat, which she said is openly anti-Jewish and has received popular support. "Until now, expressions of anti-Semitism were . . . the prerogative of the party," she said.