Portia is a powerful character. Portia pleaded the case of Antonio against he court. She wanted that Antonio should be saved at any cost. She was very intelligent. The Duke was the judge in the trial. Portia was fully prepared. First of all she tried her best that Shylock should forgive Antonio. She appealed to show mercy on him. She told him the qualities of mercy and proved that mercy is a Divine quality and the man who shows mercy is remembered and worshipped like God. But Shylock did not move a little and was adamant on his demand of a pound of flesh according to the bond.
Then very skilfully and confidently Portia allowed him to make the flesh and asked Antonio to be ready. When Shylock wanted to pierce the knife into Antonio’s chest, she warned him with a condition, “According to Bond you have full right to take the flesh but without shedding even a single drop of blood otherwise all your wealth will be confiscated by the state.’
Now Shylock was helpless. He recoils and asks for mercy. He is pardoned by the Duke conditionally. Thus, I can say that it is the skill, virtue and intelligence of Portia which saved the life of Antonio and taught a lesson to Shylock.