Michelangelo considered himself a very gifted sculptor, but was asked to paint figures for the Sistine Chapel by Pope Julius II. The Sistine chapel was completed in 1480 and was decorated by many famous panters at the time. The pope wanted to include Michelangelo to that portfolio.
It seems that Michelangelo, in his own way, allowed himself to be guided by the evocative words of the Book of Genesis which, as regards the creation of the human being, male and female, reveals: “The man and his wife were both naked, yet they felt no shame” (Gn 2:25). The Sistine Chapel is precisely – if one may say so – the sanctuary of the theology of the human body. In witnessing to the beauty of man created by God as male and female, it also expresses in a certain way, the hope of a world transfigured, the world inaugurated by the Risen Christ, and even before by Christ on Mount Tabor.
Pope John Paul II speech on April 8 1994, unveiling the restored Sistine Chapel (Full text of speech)