The rogation Sunday cantata BWV 87 is one of the most successful of the von Ziegler cantata texts. As is typical with this poet there are two biblical quotations, which generate all of the poetic text. The first is the first verse of the designated reading from the Gospel of John. In it Jesus tells the disciples that they will soon understand the difficult metaphors that he has been using. Bach sets this rather severe text in a dense imitative aria for bass with strings doubled by two oboes and oboe da caccia. The duality of God and Son emphasized in the passage is ingeniously portrayed by the fact that the countersubject is a condensation of the last half of the main subject. This gives the movement a circular, layered effect. The continuation of the countersubject is compact and detailed. These three ideas are thrown into every possible combination and key. The aria has the effect of being a tight knot, which is gradually unraveled by the next three movements.
Von Ziegler finds the biblical passage alarming rather than reassuring. It sets off a warning to pray for forgiveness. The secco alto recitative is jagged and austere, as open and barren as the previous aria is dense. The following alto aria with two oboes da caccia obbligato is one of the longest arias in all of the cantatas. It is as if the breadth is needed to explicate the tough nut of the bass aria. The musical materials are complex. The continuo alternates between isolated eighth notes and a rising arpeggio figure. The opening line of the two oboes da caccia generates from the words. The aria is unusually chromatic, even for Bach. The sound of the two oboes da caccia with the alto is so ravishingly beautiful and the harmony so rich, that clearly Bach is portraying mankind's plight and confusion as unusually compelling. The shear repetition of the "vergib" motive is bearable because of the amazing harmonic detail of its context. This motive plays unchanged throughout both the A and B sections. Although this piece was written three years before the St. Matthew Passion, the scoring, the sound and the harmonic language are identical with the arioso, "Ach, Golgatha."
After the dank oboe da caccia texture, the strings in the following tenor recitative are a warm relief. The bass again sings the words of Jesus in a brief aria with continuo. Here the texture is much more open and overtly expressive than the beginning aria. Its placement between the string recitative and string aria of the tenor is interesting. The effect is of liberating the tenor to sing his ravishing siciliano aria. It is surprising to find perhaps Bach's most sheerly beautiful siciliano in such a dour context, but the effect is of a great weight being lifted off the soul. Clearly that is the overall sense of the Gospel reading and Bach gives a better sense of this than von Ziegler. The aria is very short, but its potency gives it a climactic role in the cantata.The harmonization of " Jesu meine Freude" is connected to the music of the opening aria. It is no accident that the bass line in many of its phrases encompasses the sixth leap that is the head theme of the first aria. This is in every way an unusual but absolutely top-drawer cantata. The combination of very short and very long sections is calculated and effective. The juxtaposition of the dense style of the opening with the arias is potent and brilliantly achieved.