The Foundation of Santa Maria Maggiore

The legend behind this is a summer miracle. On the fifth of August, in the depths of a Roman heat wave, snow is said to have fallen on one hill of the city, marking out the ground where a church should stand. The pope came and traced the walls in the fresh snow, and Santa Maria Maggiore was built on that spot. Masolino painted the moment around 1423, for an altarpiece ordered by Pope Martin V, who had just brought the papacy back to a battered Rome after decades away. Up in the sky Christ and the Virgin let the snow drift down in a neat oval. Below, the pope kneels and scratches the outline into the white.