Sir Michael Tippett's 'The Mask of Time': a testament to humanity

When Sir Michael Tippett first began talking to close friends about ''The Mask of Time,'' he intimated that it would be a summation and distillation of the philosophical and musical ideas that have animated him over the past 50 years.

In fact, the monumental choral work which premiered last weekend here in Symphony Hall is all that - and something different. Here is a work decidedly, recognizably Tippettian in musical gesture, density, and sound. Yet Tippett the humanist, trying to find some promise in an age threatened with technological disaster, has finally been forced to the conclusion that there may really be no hope for man on earth.

The work, commissioned by the Boston Symphony Orchestra (BSO) as part of its centennial celebrations, has preoccupied Tippett for over three years. In world premiere performances by the BSO under the direction of Sir Colin Davis, it certainly proved the most ambitious of the orchestra's commissions - epic, provocative, and profound.

Great art should move the listener, make a person think, perhaps give a person a new insight into his views on his fellow being and the forces that animate the listener and the world. Posterity - which Tippett is not altogether sure will actually exist in the Western world - will have to find a place for ''The Mask of Time'' (and Tippett in general), perhaps even among the great musical testaments of the 1980s. In a century when faddism has been the rage, Tippett has stuck to his own path, and this latest effort reminds us how fortunate we are that a truly visionary composer has had the courage to follow those visions - whether or not they are liked, appreciated, or understood. Surely his musical ideas will have a better chance for survival than the frivolities of minimalism, the shallowness of new romanticism, and the emptiness of serialism.

Tippett will not give a classification to the piece, and rightfully so, for it cannot be called an oratorio, a mass, or any other such thing. It is not even narrative in any strict sense of the word. It is a series of ''scenes'' with fragmented texts that deal with several of Tippett's most cherished themes - first and foremost time, then his visionary brand of humanism, and finally the value of music in an increasingly technological age. The listener moves from the creation of the cosmos through the Garden of Eden and eventually to Hiroshima. Along the way we find ourselves in a jungle, on a Tuscan shore with Shelley on the last night of his life, and then in classical Greece with an actor sight-seeing before a rehearsal.

''The Mask of Time'' is in two parts; its ten sections are mostly continuous. The text is vintage Tippett, with his rather flat approach to language so that words can be ''eaten up'' (his own words) by the music. The text is largely a distillation of a lifetime of reading poetry, philosophy, fiction, and the like.

This is a dark piece, but it has sections of intense, radiant beauty, and it everywhere has Tippett's extraordinary ability to get a sound and a mood across with its own rich yet rigorous musical ethos. He rarely does the obvious - though one extended brass fanfare evokes the worst of Shostakovich. At times he may seem to stretch patience to the utmost, as in the ''Paradise Garden'' sequence, which at first hearing sounded too long. Yet on further acquaintance, this section - with its melancholic sense of a vision the speakers know will end and are therefore already lamenting - is stunningly sustained.

Tippett's dual perspective permeates the themes of the piece: Events occur in a forward-backward time plane where what preceeded and what follows are simultaneously known and commented on in relation to the present reality. The composer magically manages to get this mood across in the music as well.

The music bears the weight of binding this fragmented, snippets-of-this-and-that text all together and rendering it into a moving, cohesive whole. On first hearing, the ''Jungle'' sequence - with its spoken choral chatterings and mutterings creating a background for the soloists' contributions - proved instantly gripping. ''Hiroshima, mon amour,'' a desolate haunting bluesy chant by the soprano over a hummed choral foundation, refused to be shaken from memory hours after the performance. (Some of this strength was also due to the limpid singing of Faye Robinson and the hushed splendour of the Tanglewood Festival Chorus.) But in the course of the three times I heard the work (a final dress-rehearsal and the first two actual performances) more and more of the fabric of Tippett's monumental vision began to reveal itself for the quality material it really is.But this is almost always the case with Tippett - first hearings give only a cursory sense of what is really there.

In the end, the performance was remarkable on every count. The soloists all sounded committed throughout - Miss Robinson, mezzo Yvonne Minton, tenor Robert Tear, bass John Cheek. The Tanglewood Festival Chorus - one of the finest choruses in the land - was in top form. The BSO played with its accustomed poise and tonal richness, and the players responded to every facet of Sir Colin's conducting. The maestro has long associated himself with Tippett's music, and he knows best how to get the most out of any of the composer's scores. And Sir Colin's ties with the BSO as principal guest conductor have lead to an unusual, rewarding artistic partnership over the years. What an auspicious way to celebrate a Centennial - with a provocative work that leaves the receptive listener with a sense that something unusual has just occurred which will make him think and ponder.