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The actor, whose "Star Trek" character Mr. Spock examined the outer limits, explores the inner space of his soul when talking about his love of and concern for Israel.

Nimoy is playing a major role in "Hear, O Israel," a Philadelphia concert celebrating the 50th anniversary of Israel and featuring a lineup of such leading lights as Isaac Stern, Barbara Walters, Tony Bennett and Israeli singer Noa.

Tomorrow's event represents the first joint performance by the Israel Philharmonic Orchestra and the Philadelphia Orchestra, under the respective batons of Zubin Mehta and Wolfgang Sawallisch. The concert also kicks off a six-month national celebration of Israel's golden-anniversary year.

Nimoy will present the opening narration of the concert, which will include the inscription on the Liberty Bell: "Proclaim liberty throughout the land and to all its inhabitants thereof." The passage comes from Leviticus.

Taking note of the fact the original phrase from Leviticus includes the statement "keep holy the 50th year," Nimoy says the birthday bash is beshert — ordained.

"How appropriate that this event starts out in Philadelphia," especially during Israel's 50th year.

The actor, who first encountered fame as the detached Mr. Spock, is emotionally involved in Israel's survival. He has visited the Jewish state several times, the latest sojourn a family affair three years ago.

"It was a bar mitzvah gift for my stepson," Nimoy says.

Visiting Israel "is always an emotional trip," he says, adding that he "has always had fantasies of living there, but, at this point, it's unrealistic."

What is real is his continued commitment to Israel.

"There was a time, years ago, when you couldn't find people in my industry" eager to come out of the Jewish closet, Nimoy says. "It was a time in which name-changing [among Jewish stars] was rampant."

Today, however, "there is a greater sense of security," Nimoy says of his industry colleagues.

"And [the flourishing] of Israel has something to do with that."

That has much to do with Israel's commitment to the arts. Despite its embattled history, Israel has always made the arts, notably music, part of its profile.

Under the Bombay-born Mehta, the Israel Philharmonic has drawn international acclaim. It was founded more than 60 years ago as the Palestine Symphony Orchestra, and took the name of the state in 1949.

Nimoy has played his own instrumental role– although not on the concert stage — in perpetuating the liaison between Jews and the arts.

Spock's Vulcan greeting of "live long and prosper"– the extension of the palm, with middle and ring finger splayed — is blessed with Jewish history.

"That was taken from Orthodox Judaism," he says of the way the Kohanim, descendants of the priestly tribe, bless the congregation.

"The ritual made an extraordinary impression on me when, as a young boy, I attended those services with my family in an Orthodox synagogue," Nimoy wrote in the autobiographical "I Am Spock."

"The special moment when the Kohanim blessed the assembly moved me deeply, for it possessed a great sense of magic and theatricality.

"So it was that, when I searched my imagination for an appropriate gesture to represent the peace-loving Vulcans, the Kohanim's symbol of blessing came to mind."

Among his many roles, Nimoy has played Morris Myerson, Golda Meir's meek husband, who struggled unsuccessfully with Zionism for a share of his wife's love, in "A Woman Called Golda," a 1982 TV miniseries.

He also starred in the 1991 TV movie "Never Forget," about survivor Mel Mermelstein's marathon mission to discredit Holocaust revisionists.

Nimoy also took part in a Jewish Radio Theater presentation of "The Golem of Prague," and has been actively involved with Lubavitch's Chabad House in Los Angeles.

The actor makes a point about the importance of this opening concert and how Israel's 50th hits home.

"If ever there was a time to celebrate Israel, it's now," he says.

"It is terribly important to commemorate the country with as much spirit as possible."

He continues to play a spirited role in Jewish affairs, stressing his "concern with the fragility of our people's continuity. That is not something we should take for granted."