Some of Rafael Sanzio’s greatest painting is on the wall of the so-called Heliodoro Room in the Vatican. Covering walls with frescoes has problems that the studio painter, sitting in front of his rectangular canvas or panel, never even encounters. Here Rafael had to paint the spaces around a big door, including the one above it. He wanted to illustrate the Bible story of the escape of St. Peter from prison and not let that door break up the unity of his composition or the mood.

Here is his first idea of how to tell his story around the door.

There are three episodes, three frames, of the Bible narrative, not however in chronological order.
In the middle the angel appears to the sleeping Peter in his cell.
On the right the angel leads him out of jail right past the sleeping guards.
And on the left, just at the first violet tinge of morning in the sky, the officer who has discovered Peter’s escape, alerts the drowsy guards.

And here is the final painted version.

Rafael has discarded a strict balance of the figures left and right of the door. While doing the cartoons he has had a lot of great ideas not only for the individual figures but also for the “atmosphere” of the story.
To the central picture he added prison bars. He worked hard on the angel and the soldiers in the escape scene on the right. And he had fun painting the gleam on the sleeping soldiers’ armor.

But the real inspiration came to him for the left-hand scene.

He has given it a psychological dimension. The officer who in the sketch had been alerting the guards of Peter’s escape, is now shouting at them, threatening them. The look of incomprehension on the face of the lowest guard and the sleep-confused fuss of the one coming down the steps, fumbling with his gear, show that Rafael could invent more than placid Virgins.

But one of the almost magic achievements in this fresco is the painted light. At the top there is the bright moon in a black sky. While you look at it you might forget about color altogether and picture a cold winter night. But lower your eyes a foot and you have the dim yellow light of morning. That is another mood, another moment not strictly compatible with the black night above. And yet Rafael has made them fit together. That’s two lights. Two lights but they are only background.
It is the officer’s TORCH that lights the great scene itself. It shines on all the figures and their armor and its intensity is somehow not lessened by the other two sources of light in the picture, not confused by them. Try to paint a picture with three sources of light, each with its mood, and see what YOU get.

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