This masterpiece, one of the Museum's greatest treasures, is one of only a few original works by Caravaggio in American collections. Although he never accepted pupils, Caravaggio's enormous influence on other artists played a vital role in the development of the Italian Baroque. In this Saint John the Baptist, Caravaggio has traded idealism for what oftentimes became in his own time a controversial realism. He has literally stripped the Baptist of nearly all traditional attributes (halo, lamb and banderole inscribed Ecce Agnus Dei or Behold the Lamb of God) leaving the brooding intensity of the saint's emotional state as the subject of the painting. Saint John's solemn pensiveness is reinforced by a Caravaggio trademark: the dramatic contrast of deep, opaque shadows, playing across his body and shrouding the sockets of his eyes, with a bright light that illuminates the Baptist from above and to his right. This stark contrast of light and darkness, the brilliant scarlet of the saint's cloak and Caravaggio's placement of him in the foreground, close to our own space, all contribute to the dramatic impact of the painting. Evidence of Caravaggio's working method, in which he incised lines into the gesso ground to guide his hand while painting, can be easily seen along the sitter's left leg in the right corner. Caravaggio most likely borrowed the Baptist's pose from one of Michelangelo's seated prophets and sibyls on the ceiling of the Sistine Chapel in the Vatican, Rome.