light-imagery is ultimately
derived from the Prologue
of the Fourth Gospel:
the Gospel written by St.John,
just as the imagery
of the Spiritual Marriage
is supposed
to be derived from
the Song of Solomon.
But it must be remembered
that mystics are essentially
realists, always seeking
for language adequate
to their vision of truth:
hence the fact that they
have adopted this imagery
is a guarantee that it
represents something
which they know and are
struggling to describe.