J.S. Bach was a German composer and musician in eighteenth-century. He serves at courts. He has three most important positions. There were at Weimar, Cöthen and Leipzig. He has little responsibility at Cöthen and Leipzing. Therefore, he composed 250 sacred cantatas. The most notable one is Cantata No.140. It has seven movements. The melody and text are based on chorale tune Wachet auf. The first movement has sopranos and tenors singing a polyphonic texture. The melody and lyrics use imitation and sequence of technology. The instruments are oboes, English horn, French horn, strings, and basso continuo. The fourth movement is sung by tenors in unison. The tempo is slow. The rhythm is speedy and always repeated and varied. It expresses a relaxing
