Chapter 7 of Exodus is prologue of sorts, setting out the Lord's intentions towards Egypt and Israel. It establishes a
pattern, repeated for each of the plagues, whereby Moses or Aaron exercises God's command to trigger a curse, which
Pharaoh's magicians try, unsuccessfully, to counter. In this opening salvo, the Lord tells Aaron to cast his rod down
before Pharaoh;
(10) And Moses and Aaron went in unto Pharaoh, and they did so as the LORD had commanded: and
Aaron cast down his rod before Pharaoh, and before his servants, and it became a serpent. (11) Then Pharaoh also called
the wise men and the sorcerers: now the magicians of Egypt, they also did in like manner with their enchantments.
(12) For they cast down every man his rod, and they became serpents: but Aaron' rod swallowed up their rods.
This image is, to my mind, one of the boldest compositions to be found in medieval stained glass - three separate panels
united into a single panoramic scene. In a medium where the individual panel is nearly always a self-contained scene,
with nothing overspilling the border, the artists at Poitiers were unique in the ease with which they extended
compositional details between panels (a practice that at least one of their number, the so-called Good Samaritan Master
exported to Bourges). This is one of the most striking exammples of this technique. At either end we have the two sides
sizing each other up before the battles that would follow - Pharaoh and his magicians on the left, Moses and Aaron on
the right. The linkage between the panels is effected by their rods, here given serpent's heads
Between the two parties is a panel filled with the swirling and writhing bodies of the serpents which, as well as
illustrating the detail of the story, neatly embody the struggle to come.