Concept:The unmerciful servant was punished because he refused to show the same mercy that the king had shown him, and he mistreated his fellow servant.
Explanation:The servant owed the king a huge debt, and the king forgave him completely.
Soon after, the same servant met a fellow servant who owed him only a small amount.
Instead of forgiving that small debt, he grabbed his fellow servant and threw him into prison.
When the king learned this, he was angry because the servant had failed to be merciful.
The king then handed him over for punishment until he paid all that he owed.
Therefore, the servant was punished because he cast his debtor into jail after he himself had received mercy.
Answer:D. cast his debtor into jail