Shylock's Enemy: Antonio

Antonio

Being business rivals, Shylock and Antonio were natural enemies. However, Antonio's main business is that of a merchant, buying and selling goods and shipping them to other ports, whereas Shylock is a money-lender who makes money by charging interest on loans.
This is not Shylock's job by choice--there were a limited number of jobs which Jews were allowed to do, and this was one of them. However, Antonio has been lending money to people without interest, which cuts into Shylock's business.
It's rather like having a business competitor move in and start giving away the goods you are trying to sell. He's going to put you out of business. Antonio has other resources which enable him to lend money gratis, Shylock has not.
On top of that, Antonio is rude and condescending to Shylock just because he is Jewish. He may not be the most rude and condecending person in Venice toward Jews, but the fact that he is lumps him in with the worst offenders in Shylock's mind

Shylock's Servant: Launcelot

Launcelot

Launcelot Gobbo, a servant of Shylock, is struggling between running away from his master. A part of him which he calls "The Fiend" wants to leave while his conscience reminds him of his honest nature and urges him to stay. Although Launcelot has no reason to leave, he seems troubled by the fact that his master is Jewish, or, as he puts it, “a kind of devil”.

In Act 2, Scene 2, Launcelot confesses to his father that he is leaving Shylock’s employment in the hopes of serving Bassanio. Later in that scene, Bassanio accepts Launcelot's offer.

Later in the following scene, Shylock’s daughter Jessica bids good-bye to Launcelot. She tells him to meet with her father to make his departure more bearable. Jessica gives Launcelot a letter to carry to Bassanio’s friend Lorenzo and Launcelot leaves, almost too sad for him to say good-bye.

In Act 2, Scene 4,  Launcelot to return to Shylock’s house in order to assure Jessica that Lorenzo will not let her down. Launcelot departs and later, Lorenzo orders his friends to prepare for the night’s festivities. 

Merchant of Venice: Act 2 Scene 5

Shylock warns Launcelot that Bassanio will not be as kind as Shylock and that Launcelot will have no leeway to overeat and oversleep. 


Shylock calls Jessica and informs her that he has been called for dinner. Shylock asks Jessica to keep the doors locked and not look out at the festival taking place in the streets as he feels that trouble is brewing. 


Launcelot whispers to Jessica that she has disobey her father and look out the window for the Christian who “will be worth a Jewës eye”


Shylock asks Jessica about her secretive conversation with Launcelot and says that even though Launcelot is kind, he eats and sleeps too much to be an efficient, worthwhile servant. 


After Shylock has left to see Bassanio, Jessica bids him farewell, thinking that, if nothing goes wrong, Shylock will soon have lost a daughter, and she, a father.

Act 2 Scene 5: In Shylock's house

Relationship between Shylock and Jessica

Shylock

Jessica

The father-daughter relationship between Shylock and Jessica seems to be sound on the person-to-person level but are on a different level in terms of beliefs. 

Jessica doesn't want to remain a Jewish outcast -- whose life options are restricted and constrained-- her entire life, whereas Shylock hangs on devotedly to his religion. Therefore, making him position himself as an outcast. 

In fact, Shylock manages to turn the tables and make Christians look like outcasts. This is illustrated when he tells Jessica to protect his house and keep the sounds of the Christian celebration out of his house.

" But yet I'll go in hate, to feed upon / The prodigal Christian "

-- Shylock