not a teacher
The "four winds" refers to the winds from the north, south, east and west. As an idiom, to be "cast to the four winds" means to be thrown in all directions. In this case the writer has extended the metaphor by suggesting that when he has finished his prison sentence (served his time) he will be let out into the world and blown around like confetti, at the mercy of whatever fate awaits him.
Student or Learner