This part of the story has brought us to the fourth act of the
play, and when the curtain rises on this act we see the Court of
Justice in Venice. The Duke and all his courtiers are present,
the prisoner Antonio, with Bassanio, and many others of his
friends. Shylock is called in. The Duke tries to soften the
Jew's heart and make him turn to mercy, in vain. Bassanio also
tries in vain, and still Bellario, to whom the Duke has sent for
aid, comes not.

At this moment Nerissa, dressed as a lawyer's clerk, enters,
bearing a letter. The letter is from Bellario recommending a
young lawyer named Balthazar to plead Antonio's cause. This is,
of course, none other than Portia. She is admitted, and at once
begins the case. "You stand within his danger, do you not?" she
says to Antonio.

"ANTONIO. I do.

PORTIA. Then must the Jew be merciful.

SHYLOCK. On what compulsion must I? Tell me that.

PORTIA. The quality of mercy is not strained;
It droppeth, as the gentle rain from heaven
Upon the place beneath; it is twice blessed;
It blesseth him that gives, and him that takes:
'Tis mightiest in the mightiest; it becomes
The throned monarch better than his crown;
His scepter shows the force of temporal power,