As in his Passions (Matthew Passion, John Passion) and other oratorios (Ascension Oratorio BWV 11, Easter Oratorio BWV 249), Bach at Christmas The musical form is also used in the oratorio, and the difficulty lies in the poetic and thought-provoking lyrics. For this reason, three different lyrics types correspond to three musical forms. The original biblical texts form unaccompanied recitatives (with accompaniment in Und der Engel No. 13), recitatives and popular choruses (Turba-Chor); the lyrics of church hymns were arranged by Bach in choral lyrics (in Und der Engel No. 13) No. 7 Er ist auf Erden and No. 38/40 Jesu, du mein liebstes Leben are combined with the recitative solo); free verse (Freie Dichtungen) appears in the accompanying recitative, aria and opening chorus. In order to reduce the distance between the audience and the storyline, the complete text of the Bible is separated by free verse and hymns. The following individual musical forms can be found in the Christmas oratorio: Unaccompanied recitative: The recitative forms the backbone of the entire oratorio. According to old church tradition, a tenor plays the role of preacher, singing a recitative and expounding biblical texts. Bach composed the unaccompanied recitative based on biblical texts. A cappella here does not mean that there are no accompaniment instruments, but that only the continuo bass part serves as accompaniment. Sometimes dialogues from the Bible are sung by specific solo voices, as if they were staged dramas. For example, the role of Herod the Great is sung by a bass in the 55th song Ziehet hin, and the angel is sung by a soprano in the 13th song (Fürchtet euch nicht). To represent the speaking crowd, Bach introduced the Turba-Chor. All biblical recitatives are new compositions by Bach. In addition, there are two shorter unaccompanied recitatives that have nothing to do with the biblical text and whose function is to introduce the following chorus. In No. 22 (So recht, ihr Engel) the bass invites the angel to join the ensuing chorus of praise; in No. 63 (Was will der H?llen Schrecken nun), as in the opera's act finale, Four solo singers appear simultaneously in the recitative, leading to the closing chorus. Accompanied Recitative: A recitative accompanied by an instrument is used to introduce the following aria in content and emotion. In contrast, in Bach's other cantatas, unaccompanied recitative fulfills this function; but unaccompanied recitative is used for the preacher's music in this work, so in this It should not be used again under such circumstances. In the 14 accompanying recitatives, free verse is used instead of the biblical text. There are no regulations on its range and musical form. Therefore, Bach combined the female high chorus and the male bass duet in No. 7 Recitative (Er ist auf Erden); in No. 38 (Immanuel, o sü?es Wort) and No. 40 (Wohlan, dein Name) The bass recitative is combined with the soprano chant; in No. 45 (Wo ist der neugeborne K?nig) the alto is combined with the popular chorus. Except for the sixth part, all the other accompanying recitatives are new works by Bach. Popular Chorus: A popular chorus acts as a crowd. In his Passions and Oratorios, Bach used the form of a popular chorus to interrupt the recitative to represent the situation in the biblical text where multiple people are speaking. Thus in the chorus of angels (No. 21, Ehre sei Gott), the call of Herod the Great (No. 26, Lasset uns nun gehen) and the inquiry of the wise (No. 45, Wo ist der neugeborne K?nig) , showing a motet-style chorus. In contrast, in the presentation of the High Priest (No. 50, Und lie? versammeln), Bach had the preacher sing short passages from the Bible quoted by the High Priest. Aria: Aria forms the core of the entire oratorio, both musically and religiously. They are also composed based on free verse. The continuous plot is interrupted by these static interior monologues. There are two arias in each of the six parts, each composed of three parts. In total, five arias (Nos. 4, 8, 19, 29, and 41) are in pure A-B-A repetition form (with Da capo notation), while three arias (Nos. 31, 52, and 62) are in the form of A-B-A. Formally composed (without Da capo notation). No. 39 (Fl?t, mein Heiland) in A-B-B form and No. 57 (Nur ein Wink) in A-BCA-ABC form dominated by instrumental music are also three-section arias. No. 15 (Frohe Hirten) is a two-part aria, and No. 47 (Erleucht auch meine finstre Sinnen) consists of two parts of the same length in the shortened Da capo form.

No. 29 (Herr, dein Mitleid) is a duet, and No. 51 (Ach, wenn wird) is a trio. Among all arias, only No. 31 (Schlie?e, mein Herze), and possibly No. 51, is a new work by Bach. Arias and hymns play a particularly important role in the religious thinking of the audience, making them understand the great significance of these sacred events (Heilsgeschehen) in the holiday tradition. The solos play a specific role here: in the second and third parts, while the soprano sings the voice of the Virgin Mary, the tenor sings the voice of the faithful and the Church. Recitative: As an intermediate form between recitative and aria, recitative is similar to accompaniment recitative and is also sung with musical accompaniment. In the Christmas oratorio there are two arias for the bass, which together with the soprano chorus (Jesu, du mein liebstes Leben) form a duet (nos. 38 and 40). In the High Priest's Recitative (No. 50, Und lie? versammeln), when quoting the original biblical verses (Matthew: 2, 6), it is sung in an unaccompanied Andante recitative. The continuo part is continuously advanced by eighth notes and octave jumps, coupled with the preacher's singing melody direction, which together form a solemn effect. Opening Chorus (Eingangschor): Christmas oratorios are mainly popular for their grand opening chorus, which is the climax of the work besides the aria. The rich instrumental configuration and four-part chorus express the joy of the birth of Christ. They are typical holiday music, composed of three major keys. Contrary to Bach's other cantatas, the opening chorus here is written in free verse rather than biblical texts or hymns. The second part of the oratorio is introduced by instrumental music in the form of a pastoral (No. 10). Among the opening works, only this overture (No. 10) and No. 43 (Ehre sei dir, Gott, gesungen) are new works by Bach. Public Hymn: Even if the audience does not sing along, the public hymn still builds a bridge between the work and the audience. Hymns are outside the development of the plot and provide the audience with objective divine testimony (Heilsaussagen), while arias pay more attention to the subjective experience of each listener. With the exception of No. 64 (Nun seid ihr wohl gerochen), all other chorales in the Christmas oratorio are new works. They are known for their beautiful polyphonic music and impressive directness. The number of hymns ranges between two (parts 1, 5, and 6) and three (parts 2, 3, and 4). Bach treated these chorales in various ways. In each section, the Canticle was composed simply as a hymn, using Bach's customary compositional technique (Durchg?nge und Wechselnoten), in which a note in the chord breaks out of the chord and gradually becomes dissonant, then is rejoined equally gradually. A technique in which the original chord or the next chord is paired with essentially the same instrument part (Colla parte instrumentiert). Accordingly, most of the closing chorales display the same festive musical style as the opening chorus, and together with the former form a closure. The hymns at the end are richer in musicality than others, and are mostly accompanied by instrumental intros, interludes and outroes. No. 42 (Jesu, richte mein Beginnen) and No. 64 also feature orchestra ensembles. . Only the fifth part does not have these special orchestrations and ends with a simple hymn (No. 53, Zwar ist solche Herzensstube).