O Martírio de São Mateus

This was Caravaggio's first big public commission, finished for the Contarelli chapel in Rome by the summer of 1600, and it nearly defeated him. He had never worked at this scale or with this many figures, and X rays show he painted the whole composition twice and scrapped it before arriving at what we see. The result is violent and crowded. A swordsman stands over the fallen saint while bystanders recoil in every direction, an angel leaning down from a cloud to hand Matthew the palm of martyrdom. Look at the bearded man at the back, turning away from the killing with a stricken face. That is Caravaggio's own portrait, watching himself flee the scene he has just staged.