Read the full text of The Merchant of Venice Act 2 Scene 1 with a side-by-side translation HERE.
Portia is still at Belmont having a chat with the Prince of Morocco. He says that though his skin is darker, his blood is as red and his love as true as any pale northern guy. Still, the Prince says he wouldn't change his skin color except to change Portia's thoughts about him.
Portia, feeling magnanimous, says it isn't up to her, but if it were, the Prince would stand in her affections just like any of the other suitors (which isn't exactly a compliment given how she feels about them).
The Prince says he's very fierce, and lists off all the things he's killed. Though the Prince says he's willing to steal a baby bear from its mama bear (a very manly thing to do, apparently), all of his bravado doesn't matter. Rules are rules, and he can only win Portia through chance.
The Prince comments that in a game of dice, even Hercules could be beaten by his servant. Luck doesn't favor anybody, no matter how worthy he is. Still, he wants to take the chance to win Portia.
Finally Portia reveals that in addition to setting up this crazy lottery, her father has also placed a condition on anyone who chooses to try their luck. If a suitor decides to play the lottery of chests and chooses the wrong one, not only does he lose a chance at Portia, he must never talk of marriage to another woman again. Hearing this, the Prince insists on playing the lottery anyway, and Portia insists on having dinner.