The Board of Works for the Cathedral of Florence commissioned Michelangelo to sculpt David from an enormous block of marble left over from another project. It was commissioned with the idea that it would stand in a niche on one of the cathedral’s tribunes, way up high. When Michelangelo was finished, they realized that it was far too beautiful to be placed up high, and so it was decided to build a base for the sculpture and to place it right in front of the main government building of Florence (like putting it outside the capital building in Washington D.C.).
His perfect beauty reminds me of Pico della Mirandola, who imagines God saying to man at the creation,
“Thou shalt have the power out of thy soul’s judgment to be reborn into the higher forms which are divine.”
Here is Vasari’s description of David,
…nor has there ever been seen a pose so easy, or any grace to equal that in this work, or feet, hands and head so well in accord, one member with another, in harmony, design, and excellence of artistry. (Translated by Gaston du C. de Vere)
Remember that the biblical figure of David was special to the citizens of Florence—he symbolized the liberty and freedom of their republican ideals, which were threatened at various points in the fifteenth century by the Medici family and others. Watch a video about the importance of the figure of David for Florence.