In the Cathedral: Images & Confessions

BEWARE OF THAT WHICH IS.
BEWARE OF THAT WHICH IS NOT.
FOR THAT WHICH IS MAY GET YOU,
AND THAT WHICH IS NOT, WILL.
IF THAT WHICH IS SHOULD GET YOU 
AND THAT WHICH IS NOT DOES NOT,
THEN THOU SHALT KNOW
THAT WHICH IS, IS NOT.
BECAUSE IF THAT WHICH IS NOT,
IS WHAT I WARN YOU OF,
THEN THAT MUST BE WHAT IS,
IS NOT WHAT I WARN YOU OF, 
THEN THAT MUST BE WHAT IS NOT.
THEREFORE, I HAVE WARNED YOU.
OF THAT WHICH IS, (WHICH IS NAUGHT)
AND OF THAT WHICH IS NOT, (WHICH IS NOT)
SO BE CAUTIOUS,
TAKE HEED,
YOU ARE FOREWARNED