John the Cleaner

These are the slogans of emergency men:
  CRY FREE MANDELA the WIND bursts through
LET TAMBO BE HEARD the ROOF leaks rain
  VIVA SISULU the SKY turns blue
AMANDLA count my fingers up to TEN
  SALUTE THE FALLEN COMRADES OF GUGULETU:
These are the written sounds that cannot be spoken
A flourish on a public wall a blazing token

O John the Cleaner I can hook you with letters
  Make the great mystery of script banal
I of your ruthless elders and skilled betters
  Who cannot understand your pidgin-taal
JESUS IS KING you say and I say Break your Fetters
  A thousand ks between the castle and the kraal
You've set out to read the words OFFICE TO LET
How can I escape the prison of the alphabet?
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