The words are capable of division into two short sections: Misericordias Domini (the mercy of the Lord), cantabo in æternum (I will sing for ever), but the division is not a real one. For there can be only one fundamental idea—either "Misericordias Domini" or "cantabo in æternum." If the former, then the "cantabo" should be subordinate; if the latter, the "Misercordias" must be included in the exultation. Mozart has so far given way to the love of the picturesque, to which Handel also made many sacrifices, that the "Misericordias" is to be sung softly, but the "cantabe in æternum" energetically and in a lively fugued passage. When the last motif has been worked out, the Grave is repeated, and then again the fugue.
It is evident that the law by which thoughts are expressed in speech does not altogether apply to musical expression, but that with the introduction of a new element new rules are CHURCH MUSIC. imposed. Since the words, intelligently interpreted, give the keynote to the whole conception, it is the musician's task to embody the sentiments inspired by them in such forms as he has at his disposal. The necessity for avoiding contradictions or inconsistencies is no barrier, but rather an incentive to his creative energy. But a contradiction may arise not only from a misconception of ideas, but from the undue prominence of some one point which, detached from the context, injures the effect of the whole. This would be the case here, if, as Thibaut seems to indicate, the idea of the mercy of God, and that of the praise offered to it, were treated in absolute opposition and mechanical alternation one with the other. But this is not so. The motifs given to the words "cantabo in ætemum," both in themselves and in their working-out, express nothing but firm conviction and desire to act upon that conviction; we seem to view the spiritual condition of a human being who, in spite of adverse fate and sorrowful experiences, is never weary of praising the Lord. The "cantabo" is placed just as Thibaut demands that it should be, as a contrast to the "Misercordias Domini and the contrast is so harmoniously expressed and so consistently sustained as in no way to injure the musical effect of the work as a whole.[ 50 ]
A very interesting composition, belonging to the year 1776, is the Offertorium de Venerabili (260 K.), "Venite populi," for two choruses, scored in eight parts.[ 51 ] It is imitative throughout, less strict in form than usual; the voices seem to take actual delight in their free movement; the two choruses and the separate parts are clearly divided while maintaining natural relations with each other, and the whole work is sharply cut and characteristic both in harmonies and in rhythm. The principal movement is divided in the middle by a short, slow movement, having the same motif, but in different combinations.
A "Sancta Maria, mater Dei" (273 K.), for chorus, composed in September, 1777, and an "Alma redemptoris mater" (277 K.), for solo and chorus, of about the same date, judging by the style, are very differently conceived: they are simple in design and in treatment, quiet and mild in expression. Delicate lights and shades betray the hand of a master conscious of his power to stir the feelings and satisfy the sense of beauty of his hearers. Equal genius is displayed in the selection of simple meins, and the ease with which the right effect is given at the right moment; and every now and then a delicate harmonic inflection, or a charming little motif in the accompaniment, leaves us in no doubt as to Mozart's individuality.[ 52 ]
The survey we have taken of Mozart's church music will give some idea of the industry with which he strove to master the various forms of his art, as well as of the ease and fertility of his production, and the truth of his artistic feeling. Remembering his activity in operatic music, we are amazed at the wealth of his many-sided genius; but the unceasing exercise of all his musical powers serves to explain in part that marvellous acquaintance with all the technicalities and forms of his art which not even the possession of great genius can account for in so youthful a composer.
External circumstances influenced not only the conception and treatment of church music, but the means at disposal for its performance. Mozart's chief dependence in Salzburg was on the chorus, as is shown in a letter (November 4, 1777), where he says that none of his masses can be performed at Mannheim, because the chorus was bad, and the orchestra must be the first consideration. This is confirmed by the works themselves, of which the choruses are always the main substance; Mozart found his materials ready to hand in the carefully instructed church singers and chapel choir. He had himself received vocal training. Even as a boy the correct delivery and good management of his voice excited CHURCH MUSIC. astonishment; and though he lost his voice on attaining manhood, his intercourse with trained singers gave him an accurate knowledge of the voice and its treatment. Careful as Mozart is to arrange each part easily and conveniently for performance, yet he always reckons on well-trained singers, and even exacts from the choristers, where occasion requires, not a little skill in taking intervals and in execution and intonation. Above all, he demands the intelligent delivery of a singer who knows how much depends upon it.
The treatment of the solo voices as regards execution does not differ in church and operatic music. Frau Haydn and Meissner, Marie Anna Braunhofer and Jos. Spitzeder, had received good practical training, but they were not such remarkable performers as to call forth new or original creations. When the solo voices are not treated with a view to executive display they are altogether in the style of chorus parts.
The organ, as the instrument appropriate to the church, invariably accompanies the singing, so that in all Mozart's church compositions the bass part is carefully figured, sometimes by his father's hand; it is sometimes, but rarely, employed obbligato, as in the Benedictus (259 K.), and then treated in easy style. Next to the organ come three trombones, essentially the support of the chorus, played in virtue of his office by the "stadtthürmermeister" and two of his subordinates. [ 53 ]
Following ancient tradition they sounded in the tutti in unison with the three lower voices of the chorus; the trombones were generally left unindicated in the score, and only the places marked where they were to be silent. This curious prominence of the brass instruments, whereby the soprano part is left unrepresented, was usual at that time, and could not be dispensed with in the church. Trombones are seldom used independently by Mozart, and then in the simplest manner.