Ezra Laderman's Symphony No. 5 ("Isaiah") is a work of overwhelming drama, superbly organized structures, orchestral writing of the highest virtuoso quality and deeply stirring--ultimately very satisfying--emotional tension and release. It sounded like a masterpiece in last night's world premiere performance by the National Symphony Orchestra.

The symphony was not only composed for but very precisely tailored to the temperament of Mstislav Rostropovich, and it was clearly and successfully designed to evoke greatness in the National Symphony. Soprano Lucy Shelton, who had only a week to prepare her very demanding part, made it sound as though the music had been composed for her.

The symphony is essentially based on the reconciliation of opposites: themes of war and peace. Its opening movements are filled with tensions--a multitude of motifs jostling one another and undergoing transformations in the opening adagio; driving, pounding, muscular rhythms in the magnificently orchestrated scherzo that follows. The third and final movement introduces Shelton singing five passages from the Book of Isaiah--in English for this occasion, though the composer has also prepared versions in Russian and Hebrew.

Two words remain in Hebrew for any performance: "Yad Vashem" ("memorial and name"), which is also the name of Israel's memorial to the victims of the Holocaust. Laderman's setting of these words, repeated over and over with a variety of elegiac melodies, brings the work to the most powerful though by no means the loudest of its many climaxes, leading into a long, slow, quiet fadeout on the words "Nation shall not lift up sword against nation, neither shall they learn war any more," and the final injunction: "Let us walk in the light of the Lord."

The device recalls the end of Mahler's "Das Lied von der Erde" and attains a comparable power. Shelton sang with a purity of tone, a verbal clarity and a depth of emotion that matched the great performance by Rostropovich and his orchestra.

The evening opened with a fine reading of Arthur Foote's neglected, enjoyable Suite for String Orchestra in E. In Mozart's 27th Piano Concerto, Walter Klien's immaculate solo was very closely matched by Rostropovich's sensitive conducting. Rostropovich's growing mastery of Mozart is an index to his phenomenal growth as a conductor during this season.