The "casting out of a demon" must refer to an actual change.
The blindness may refer to his inability to see truth;
that he can now see may refer to his new allegiance.
That he can now speak may point to his new role,
as an ambassador for the embryo movement.
The authorities are unconvinced;
saw his message as dangerous and of the devil.
Perhaps a threat to them or their way of living;
the dominant role of a politicised priesthood;
the subservience of religion to Rome.
Perhaps forseeing the horror of war
and armed rebellion.
Perhaps they were right for that followed
only thirty or so years later.
but it did not arise from
the message of Jesus.