In some of his most special work, for some special occasions, Mozart demonstrates the deepest humanity and human struggle which is not often heard in the Classical Period. This kind of work became the greatest and most touching in his time and His Requiem K.626 fits into the category. In this article discussion is made to explore Mozart's mind when he composed his Requiem, especially in the aspect of 'Life Education' and the 'Studies of life and Death'. This work is strongly related to the mind state of dying people. Mozart expressed honestly the fear, helplessness and sorrow of such dying people, and furthermore the eager hope of redemption or the relieved state of mind after the process of death started. The power of this piece is so strong that it is reasonable to assume it comes from Mozart's own experience before his death without finishing the whole piece.