Ever since his pre-Juilliard days as a philosophy major at Cornell, the composer Steve Reich has never shied away from big ideas. Nor has the self-confirmed "power talker" ever shown much reticence over language. Much of his reputation, in fact, has come from the way in which he singularly matches the inner sensuality of the spoken word with music that austerely illuminates its content.

Reich's fascination with language will soon be the theme of his 70th birthday celebration at Lincoln Center, which highlights two very different approaches to vocal music: the first with Grant Gershon conducting Reich's choral works with the Los Angeles Master Chorale, the second featuring the Steve Reich Ensemble performing the composer's 1993 multimedia opera, The Cave. "Basically, I look for a text that gets me going," he says. "And for each of these evenings, that means very different things."

From his early tape works to his process pieces with larger ensembles, Reich's output has emerged as one of the most organic musical catalogues in recent history. In the case of You Are (Variations), a Lincoln Center co-commission receiving its New York premiere on October 28, the composer's search for texts results in a veritable summary of his personal and professional life to date. "My whole attitude was," he admits, "instead of trying to do something new and different, to go back and do the things I already knew how to do."

Indeed, listen to the Los Angeles Master Chorale's recording of the piece on Nonesuch and you can hear the pulsing chords from Reich's 1970s works, his long-standing love of early-music textures, his way of spinning ancient canonic structures into avant-garde gold. But most of all, You Are is about the words — particularly the juxtaposition of Hebrew texts and Wittgenstein's Philosophical Investigations that have served as spiritual and intellectual touchstones throughout Reich's adult life.

"The major difference between Tehillim [which shares the October 28 program] and You Are is the length of the texts," he explains. "I didn't use much repetition for Tehillim because those Psalms are fairly lengthy and repetition wouldn't have been appropriate. But the brevity of the texts in the You Are (Variations) calls out for a lot of — as the title says — variation."

The texts, simple enough to fit on the proverbial matchbook, open with "You are wherever your thoughts are," an English translation of a quote from the 18th-century Hasidic mystic Rabbi Nachman that Reich likens to the art of listening to music. From that somewhat ethereal plane, the piece comes sharply back into focus with "Shiviti Hashem l'negdi" ("I place the Eternal before me"), a harmonically darker section where the composer consciously sifts through the pieces to see what's really important in life.

Reich describes his third text, Wittgenstein's reflective "Explanations come to an end" as "practically an outtake from Three Tales," his millennial multimedia opera with his wife, video artist Beryl Korot, on the limits and perils of technology. "Look at Einstein and Newton and on one level you can clearly see what they're saying," he says. "But there were still plenty of things they didn't know. Certainties are temporary — historical and scientific discovery still goes on."

His fourth Variations text, "Say little and do much," looks to the Talmud. "The sentiment is very pragmatic — very American," he says. "But it's also very Judaic." Unlike Tehillim, however, a text-first immersion into the Hebrew Psalms that yielded richly unpredictable rhythms, Reich's decision to use the original Hebrew stemmed first from the melodic potential. "The words 'do much' end so abruptly," he explains. "If you say, 'Ehmor m'aht, v'ahsay harbay,' you get some really beautiful vowels that can stretch into long melodic passages that better illustrate the text."

That statement marks a small but crucial difference between Reich's recent direction and earlier works like The Cave, his first collaboration with Korot, which was last seen in New York during Lincoln Center Festival's 1999 Reich retrospective. For The Cave, Reich and Korot interviewed an assortment of Israelis, Arabs, and Americans about a wide range of shared references, not least their connection to Abraham, the patriarch of both Muslims and Jews.

"This wasn't just setting texts, this was setting a series of human beings," says Reich, referring to the images of his subjects that are projected on a series of video screens. "It was documentary reality melding into musical reality. You see these people as well as hear them, and as far as my music is concerned, as they spoke so I wrote. My melodies came entirely from them. The drama came from them. There are live singers on stage who essentially offer comment, but the primary action always comes from the screen."

The results reveal a family feud of Biblical proportions, which Americans from their geographic and cultural remove are barely able to grasp. "I wrote The Cave back when the first Gulf War was happening, and I was getting some pressure at the time to finish it right away while it was still topical," he recalls. "Even at the time, I told them, 'Relax.' And unfortunately, the piece still retains its relevance."

Although Reich usually downplays a composer's role in society as either philosopher or statesman (during his 60th birthday celebration he claimed, "The idea that The Cave can help peace in the Middle East is absurd") he does maintain that if a subject resonates strongly enough with the artist it will resonate with the audience as well.

So just how does the composer feel about The Cave today? "We walked on eggshells at the time because Salmon Rushdie had shown us what happens when you say things that Muslims disagree with," he says. "I bent over backwards to be accommodating.

"But I was finishing The Cave during the first World Trade Center bombing. I was living four blocks from the World Trade Center on September 11, a day that was truly terrifying for any New Yorker. And today that makes me look at the Second Act in a very different light. Now it looks exceedingly polite. Perhaps too polite."

Ken Smith is the U.S. correspondent for Gramophone and the Asian performing arts critic for the Financial Times.