Antonio and Bassanio have a very strong relationship in Act 1 and we can infer that they have been friends for a long time as Bassanio says that he already owes Antonio ‘the most in money and in love’ (1:1). When Bassanio asks Antonio for support, Antonio assures him that ‘my purse, my person, my extremest means/ Lie all unlocked’ to him’ (1:1).
Bassanio and Antonio remain very close as Act 1 progresses, however they begin to have differing opinions when the issue of Shylock’s bond emerges.
When Antonio asks Shylock for money (to lend to Bassanio) and Shylock insists that Antonio must give him a pound of his flesh if he can’t repay the sum on time, Bassanio urges Antonio not to sign: ‘You shall not seal to such a bond from me’ (1:3). Antonio is happy to commit to the bond for his friend, however Bassanio is much more uncertain.
Some distance grows between Antonio and Bassanio as Bassanio leaves Venice and his friend in order to go to Belmont and woo Portia. However, when Bassanio receives a letter detailing Antonio’s lost ships, he is full of concern and explains to Portia that Antonio is his ‘dearest friend’ (3:2). Antonio’s letter reveals that he is not sure whether his friend will come to visit him or not, as he writes ‘use your pleasure’ (3.2) suggesting that Bassanio does whatever he wants to do.
In Act 4 we see Bassanio and Antonio’s relationship restored. In the court room, when Antonio is about to face death, Bassanio does all that he can to try and dissuade Shylock from claiming the pound of flesh.
Bassanio and Antonio are very close once more when we reach the end of the play.
We see just how much influence Antonio has over his close friend when, after Antonio has been saved, Portia (as ‘Balthasar’) asks for Bassanio’s ring. Bassanio refuses when she asks for it, however when Antonio asks Bassanio to give it over, Bassanio does so.