This painting, 'The Seven Works of Mercy' by Caravaggio, is the reason I walked all across the city one Sunday afternoon. I love Caravaggio and I'd never seen this canvas. Painted in 1607 for the church of Pio Monte della Misericordia, it's still in its original location. Because of the distance I had to stand from the painting in order to take this picture, you are forgiven if you're unable to spot all seven of the corporal works of mercy: Feed the hungry, give drink to the thirsty, clothe the naked, shelter the homeless, visit the sick, ransom the captive, bury the dead. Originally the project (for which the painter was paid extravagantly) was to have been seven paintings, each with one work of mercy, positioned throughout the church. Instead, Caravaggio incorporated all seven into the one altarpiece. One-stop shopping.