This part of the parable reveals the utter heartlessness of the forgiven one. Again, put yourself into this and see if the shoe fits. It is utter disregard of his obligation to emulate the example of his lord.
The contrast is shown in that he was owed the paltry sum of what amounted to $12.00 American. A sum that was all out of proportion to what he owed his lord, but he tried to exact a mere pittance from his companion. He took him by the throat! What an illustration. That is pretty hard-hearted. You see, just like the students, how quickly he forgot the grace that had been extended to him; how quickly he forgot the grace that was given him and put him under the obligation to manifest the same kind of grace to others.