the fountain art, With faith sustain our heart, That at the last we hence in peace depart. Have mercy, Lord.BWV 669 Kyrie, Gott Vater (Kyrie, O God, Eternal Father) BWV 669 is a chorale motet for two manuals and pedal in time. The four lines of the cantus firmus in the phrygian mode of G are played in the top soprano part on one manual in semibreve beats. The single fugal theme of the other three parts, two in the second manual and one in the pedal, is in minim beats and based on the first two lines of the cantus firmus. The writing is in alla breve strict counterpoint, occasionally departing from the modal key to B and E major. Even when playing beneath the cantus firmus, the contrapuntal writing is quite elaborate. The many stile antico features include inversions, suspensions, strettos, use of dactyls and the canone sine pausa at the close, where the subject is developed without break in parallel thirds. Like the cantus firmus, the parts move in steps, creating an effortless smoothness in the chorale prelude.BWV 670 Christe, aller Welt Trost (Christ, Comfort of all the world) BWV 670 is a chorale motet for two manuals and pedal in time. The four lines of the cantus firmus in the phrygian mode of G are played in the tenor part (en taille) on one manual in semibreve beats. As in BWV 669, the single fugal theme of the other three parts, two in the second manual and one in the pedal, is in minim beats and based on the first two lines of the cantus firmus. The writing is again mostly modal, in alla breve strict counterpoint with similar stile antico features and a resulting smoothness. In this case, however, there are fewer inversions, the cantus firmus phrases are longer and freer, and the other parts more widely spaced, with canone sine pausa passages in sixths.BWV 671 Kyrie, Gott heiliger Geist (Kyrie, O God the Holy Ghost) BWV 671 is a chorale motet for organum plenum and pedal. The bass cantus firmus is in semibreves in the pedal with four parts above in the keyboard: tenor, alto and, exceptionally, two soprano parts, creating a unique texture. The subject of the four-part fugue in the manuals is derived from the first two lines of the cantus firmus and is answered by its inversion, typical of the stile