n January, 1779, after eighteen months searching for a job in Mannheim and Paris, Mozart came home to Salzburg empty-handed. He had undertaken this long trip at his father's urging, to look for a major court position worthy of his extraordinary gifts. But not only had he failed to land a job; he had turned down as uninteresting the only one he was offered, the post of court organist at Versailles. While in Paris, his mother, who had accompanied him, suddenly became ill, her condition quickly grew critical, and a few days later she died. Leopold Mozart, at once heartbroken and furious, blamed his son for her death. Yet Mozart stayed on in Paris for two more months until finally, in response to rising anger from his father, he wended his way homeward. On the way he spent several weeks in Munich, where he proposed to Aloysia Weber, a dazzling soprano who had swept him off his feet in Mannheim. But she had found another man.

Nevertheless, despite these personal tragedies and professional setbacks, the trip — from a musical perspective — marked the turning point of Mozart's life. In Mannheim he encountered a level of music-making so superior to Salzburg's that it fundamentally altered the way he composed. Mannheim's orchestra could play anything he could imagine writing; he wrote Leopold that they sounded like "an army of generals" — especially their wind players. Hearing what these instruments were capable of in the hands of such musicians, from then on his own woodwind parts became freer, more expressive, and certainly more demanding. But when he got back to Salzburg, he faced the same obstacles that had sent him away in the first place: the city itself was a provincial backwater, and its ruler, Prince-Archbishop Heironymus Colloredo, was a man whom both Leopold and Wolfgang despised. It would be two more years before Mozart could break free and take up life as a freelance musician in Vienna.

Meanwhile — thanks to delicate maneuvering by Leopold — he was named court organist, a position which also required him to compose sacred music for the cathedral. A few weeks after arriving home, he wrote the Mass in C Major, K.317 ("Coronation"), for Easter Sunday (the work acquired its nickname when it was performed for the coronation of Leopold II, in 1791). This Mass was one of several extraordinary works which he somehow managed to create during this immensely frustrating time. Others included the Vesperae solenne de Confessore, K.339; his first operatic masterpiece, Idomeneo, K.366; and a work perhaps intended for joint performance with his father, as a kind of peace offering: the Sinfonia Concertante for Violin and Viola, K.364/320d.

Archbishop Colloredo, an "Enlightened" prince of the church, insisted on strict rules for liturgical music, the same rules promulgated by Emperor Joseph II in Vienna. Their aim was to focus attention on the Mass itself and away from what was perceived as musical ostentation. Of course, this infuriated musicians. As Mozart wrote to his Italian mentor and friend, Padre Martini:

Our church music is very different from that of Italy, all the more so because a complete mass ... even the most solemn ones, when the Prince-Archbishop himself presides, may not last more than three quarters of an hour. One needs particular training for this kind of composition; and furthermore it must be a mass with all instruments — trumpets, timpani, etc.

Mozart's task in 1779, then, was to compose a full-scale Mass with soloists, chorus, and orchestra, a work suitable for Salzburg's massive cathedral and written in a style appropriate to the splendor and joy of Easter Sunday — all in less than forty-five minutes. He managed to do it in less than thirty. The solution was the same used by Haydn in his later Masses and by Beethoven in his early Mass in C Major: treating the four soloists as a quartet rather than assigning them individual arias; setting words homophonically instead of polyphonically; and replacing the traditional fugues at the end of the Gloria and Credo with quick, sharp chords.

From its opening bars, the Coronation Mass sparkles with bright orchestral colors and driving energy. The majestic dotted rhythms of the Kyrie become even more triumphant with the addition of brass and timpani. The Gloria explodes in a fast, dancelike triple meter, opposing choral tuttis to passages for vocal quartet and climaxing in dramatic solo-tutti exchanges at the final Amen. The Credo also opens with choral declamations, this time surrounded by rushing violin figures and joyful blasts from brass and timpani. Then, suddenly, there is a kind of quiet musical genuflection at the words, "And he was incarnate by the Holy Spirit of the Virgin Mary, and was made man" (Et incarnatus est de Spiritu Sancto ex Maria virgine, et homo factus est). Here, where worshippers were expected to kneel, the harmony shifts magically into E-flat major as the solo quartet sings softly and slowly, to the angelic accompaniment of muted violins. The triple-meter Sanctus is marked maestoso ("majestically"), its strong rhythms underscored by brass and timpani. The Osanna, brisk and joyful, contrasts with the vocal quartet's gentler, duple meter Benedictus.

For the Agnus Dei, Mozart breaks this Mass's format with a transcendent aria for soprano. Written in pastoral style, this is his moving response to the image of Christ as the Lamb of God (Agnus Dei). With its graceful tempo and 3/4 meter, pizzicato cellos and basses, and songful countermelodies for oboes and violins, this aria invites us into a peaceable kingdom, where the sins of the world are forgiven (qui tollis peccata mundi). Later, Mozart would use this same music (changing its meter to 2/4) for "Dove Sono," the Countess's lament in Act II of The Marriage of Figaro.

While the Mass in C Major was meant for the triumphant celebration of Easter, Davidde penitente (The Repentant David) was written for a Lenten benefit concert. Its premiere by the Viennese Society of Musicians (Tonkünstler-Societät) on March 13 and 15, 1785, was conducted by its composer, "Sig. Amadeo Mozart." Mozart had tried since 1783 to join the Society, which supported the widows and orphans of deceased musicians, but it never accepted him, ostensibly because he failed to submit a certificate of baptism, which — for unknown reasons — he never got around to requesting from Salzburg. On numerous occasions from 1783 through 1791 he furnished music for the Society's concerts, but they never let him in. After his death, Constanze Mozart had to petition the Emperor himself for some degree of support. Thankfully, he obliged.

Davidde penitente is a rarely performed though quite extraordinary work. The author of its Italian texts — loose paraphrases of portions of the Lenten Penitential Psalms — is unknown. Lorenzo da Ponte (librettist of The Marriage of Figaro, Don Giovanni, and Così fan tutte) has been suggested, but without evidence to support it. One wonders if Mozart encountered these texts during his travels to Italy in the 1770s, or if a friend in Vienna might have given them to him; they seem suited for private devotions.

Mozart received the commission on February 11, 1785. The timing could hardly have been worse. Here, adapted from Otto Erich Deutsch's Mozart: A Documentary Biography, is a sampling of his schedule during that period:

Looking at this packed calendar, it is no surprise that in fulfilling this commission, Mozart resorted to a contrafactum — setting new words to music he had written before. The work he recycled was his magisterial, though unfinished Mass in C Minor, K.427/417a, composed for Salzburg in 1782/83. In addition to his haste, there could have been two other reasons for this sleight-of-hand. First, Viennese audiences had never heard the C-Minor Mass and he may have wanted them to hear it — justifiably so, for it belongs with Bach's Mass in B Minor and Beethoven's Missa solemnis as one of the greatest sacred works ever penned. Second, until the Requiem was commissioned shortly before his death, Mozart was never asked to compose sacred music during his ten years in Vienna. He may have taken this opportunity to demonstrate his mastery of the idiom, and at the same time, perhaps, to solicit potential commissions.

Mozart finished only two movements of the Mass in C Minor, the Kyrie and Gloria, so it was these that he borrowed for the cantata. Fortunately, this Mass, unlike the "Coronation," is in cantata-style, like Bach's B-Minor Mass, meaning that each movement is subdivided into separate numbers — aria, chorus, ensemble, etc. This made it relatively simple to substitute the ten short Psalm paraphrases for the original Latin words of the Mass. The C-Minor Mass is also a dark-hued, solemn work, making it well-suited to a Lenten concert and to the Penitential Psalms for which it was adapted.

The Kyrie of the Mass in C Minor became the first of the Penitential poems. The Gloria, a much longer text, is spread over the remainder of the cantata except for movements 6 and 8. These are newly composed arias for tenor and soprano I, respectively. Soprano II performs the Laudamas te from the Mass, now set to the words, "Lungi le cure ingrate, ah!"; and joins soprano I for the Dominus Deus duet, now "Sorgi, o Signore." The three soloists together perform movement 9, the Mass's florid trio, Quoniam tu solus sanctus, now "Tutte le mie speranze." The fact that three outstanding singers were available for the Society's performances allowed Mozart to borrow solo and ensemble portions from the Mass as well as to supply the new arias for the two vocal stars: Johann Valentin Adamberger and Caterina Cavalieri. He knew them both very well — they had performed leading roles in his highly successful opera, The Abduction from the Seraglio (1782).

Both Adamberger's "Ah te, fra tanti afanni" and Cavalieri's "Fra l'oscure ombre funeste" are two-tempo arias, a format very popular in Vienna at that time. The first section is slow, with long, expressive melodic lines, while the second is characterized by wide leaps and rapid-fire coloratura. The tenor's aria, in pastoral style, provides a fine example of Mozart's post-Mannheim woodwind writing, with its exquisite concertini for flute, oboe, clarinet, and bassoon. This marks the only appearance in tonight's program of the clarinet — a new instrument during his lifetime — since there were no clarinets in Salzburg.

In the end, however, it is the choruses in Davidde penitente, all taken from the Mass in C Minor, that seem most memorable. During the period that Mozart was working on that Mass he was spending every Sunday morning at the house of the Baron van Swieten, playing and conducting music by Bach and Handel. The unmistakable influence of these masters is everywhere apparent, culminating in the towering fugue from the Mass's Gloria that brings Davidde penitente to a close. Only in the last months of his life would Mozart have another chance to write music in this powerful, densely contrapuntal style. That work, the Requiem, would also remain unfinished.

Roye Wates is Professor of Music at Boston University, with a specialty in the operas of Mozart. She holds her Ph.D. in Music from Yale University.

Professor Wates has written so wisely and well about the two works in tonight's program that I find little to add except some further remarks about orchestration and, in the case of Davidde Penitente, a word or two about what she politely (correctly) calls "contrafactum" and I, less politely, "recycling."

In the eighteenth century and earlier, trumpets and drums signified celebration. Even in a modest-sized orchestra, the addition of those timbres created a dimension of splendor that spoke of a very special occasion. Without the trumpets and timpani, Mozart's 1779 Easter Mass, only later dubbed "Coronation," would have been supported by an orchestra that was modest indeed in sound and size. There are only seven independent parts: two oboes, two horns, two violins, (no violas, as was customary in Salzburg), and cello/bass (one real part). The addition of brass and drums really raises the temperature, creating from small forces a piece of liturgical grandeur.

What about the three trombones you see on the stage? Generally, in choral music of the period, composers doubled the three lower chorus parts with trombones. One suspects, though, that this was more a matter of reinforcing insecure singers than an attempt to expand orchestral color. Some modern performances dispense with the trombones. However, in the cantata Davidde Penitente, the trombones occasionally have obbligato (independent) parts and are thus essential to the orchestration; the violas also rejoin the orchestra.

The Great Mass in C Minor, like the Requiem, is an incomplete masterpiece. Complete or not, these two choral works represent the apogee of Mozart's creativity in that genre. In the eighteenth century, and earlier, there was no pejorative implication to a composer adapting an earlier work of his own, or of another's for that matter, to a different purpose. Handel did it all the time. Many of the movements of Bach's B Minor Mass were created out of earlier composed cantata movements, sometimes extensively rewritten, often only slightly adjusted to accommodate the different text. It is somewhat rarer, and not an inconsiderable feat (!), to adapt a multi-movement work to an entirely new text without making major musical alterations. Art aside, just as an example of virtuoso text transferal, Mozart's work on Davidde Penitente is impressive.

Professor Wates has detailed the circumstances surrounding Mozart's decision to recycle his Mass into the cantata Davidde Penitente. I will remark on some of the performance imperatives that have emerged as my colleagues and I have prepared this remarkable work - how we have discovered an almost entirely new work here, familiar in countenance yet unfamiliar in detail. It seems to me that by removing the music from its liturgical environment, Mozart invites an investigation of different dimensions of expression. And because the music is Mozart's, those dimensions justifiably lead to a more dramatic/operatic interpretation than would be desirable or permissible in a liturgical work of that period.

The music, with the exception of the two added solo movements, is the same as in the corresponding movements in the Kyrie and Gloria of the Mass. Reconciling the exultant moments in the Gloria with the introspective texts of Davidde is one of the major interpretive decisions one must make in performing it. Take, for example, the Laudamus te, one of Mozart's most brilliantly extroverted works for mezzo-soprano. In Davidde, a more ruminative text to the same music means rethinking the whole aesthetic nature of the piece. Another example: the choral "Gratias" (We give thanks) in the Mass becomes "a pietà:" (have pity) which invites a more personal and urgent kind of declamation from the chorus. Examples abound.

For those who know the Great Mass in C Minor well, many moments in Davidde will surprise, perhaps shock. The Mass with all its variety of textual moods is still a Mass, a liturgical concept, while Davidde, though penitential in tone and biblical in inspiration offers different opportunities. Mozart, the first great Romantic opera composer, explored vast new worlds of vocal expression — the two interpolated arias in Davidde give ample evidence of that aspect of his genius. The C Minor Mass offers wonderful hints of that world. Davidde offers the opportunity to go a little further: to re-cycle, re-explore, and re-invent; to make something quite new from an already perfect, if unfinished work of art.

The Boston Cecilia performs this work at New England Conservatory's Jordan Hall in Boston on April 10, 2005.