One of seven panels of a polyptych that Sassetta made for the high altar of San Francesco, Borgo Sansepolcro (i.e. the San Sepolcro Altarpiece). The series depicts the life of St. Francis, founder of the Franciscan Order, who died in 1226.
Something about this composition — how the light strikes the stones; the apparition of a fantastic and one-dimensional Christ in the sky; the downright bizarre landscape — lends a “modern” tone. It’s almost surreal, from my vantage.
Also from my vantage, the red sign atop the crucifix realllly looked like Chinese. Spoiler alert: it is Latin. Everyone is having visions today.