The Cantata BWV 23 was one of the two works submitted by Bach in his application for the cantor's job at Leipzig. The other work cantata BWV 22 is light and not particularly intellectually demanding. BWV 23 is one of the densest and greatest of all the cantatas. The duality of Christ's human and divine identity is characterized by the two oboes d'amore and the two high voices. The thorny, even awkward juxtaposition of triple and duple meters in the opening duet is a brilliant portrayal of the difficulty of the human and the divine inhabiting one body. The tenor recitative is accompanied by strings. Laid on top of it is the modal chorale tune "Christe du Lamm Gottes." The large chorus that follows is in a rondo character. The chorus alternates with a tenor-bass duet. The tenor and bass give the effect of balancing the soprano and alto that opened the cantata. The cantata ends with one of Bach's greatest and profoundest chorale fantasias, a setting of the German Agnus Dei. The chorale begins with some of the weightiest and most ponderous music that Bach ever composed. One is almost unaware how the guilt is lifted throughout the movement which ends with a lightness and transparency never anticipated by the opening.