The little window over the Piscina tells of the vision of Isaiah (Isaiah
vi. 11). “Then flew one of the seraphims, having a live coal in his
hand, which he had taken with the tongs from off the altar: and he laid
it upon my mouth, and said, Lo, this hath touched thy lips and thine
iniquity is taken away, and thy sin purged.” Close to this little window
is the Holy Table, from which is to be daily given the body and blood of
our Lord Jesus Christ for the preservation of body and soul unto
everlasting life, and it has seemed appropriate to tell nearby in stained
glass the story of that earlier cleansing by the coal from off the altar.