On Signorelli’s Fresco of the Resurrection

I saw a vast bare plain; with, overhead,
A half-chilled sun, that shed a sickly light;
And all around, till out of reach of sight,
The earth’s thin crust heaved with the rising dead,
Who, as they struggled from their dusty bed,
At first mere bones, by countless years made white,
Took gradual flesh, and stood all huddled tight
In mute, dull groups, as yet too numb to dread.
And all the while the summoning trump on high
With rolling thunder never ceased to shake
The livid vault of that unclouded sky,
Calling fresh hosts of penitents to take
Each his identity; until well-nigh
The whole dry worn-out earth appeared to wake.