ANTONIO I pray you, good Bassanio, let me know it; And if it stand, as you yourself still do, Within the eye of honor, be assured My purse, my person, my extremest means Lie all unlocked to your occasions. (1.1.142-146)
Antonio is willing to do anything to help his friend, including loaning him the money to woo Portia. What's interesting is that Antonio says that it's not just his "purse" (wallet) that's "unlock'd" for Bassanio's use; he is also making his entire "person" available to his friend, which may suggest a sexual relationship.
ANTONIO Well, tell me now what lady is the same To whom you swore a secret pilgrimage, That you today promised to tell me of? (1.1.126-128)
Bassanio's love life is the first thing Antonio brings up with Bassanio when they're alone together in the play. Maybe he's just one of those guys who likes to gossip, or maybe Bassanio has been on his mind. Bassanio's new courtship seems likely to be the source of Antonio's sadness, as it's at the forefront of his mind. Antonio clearly cares deeply about Bassanio as a friend, and he's facing the fact that he might lose him to this woman.
BASSANIO To you, Antonio, I owe the most in money and in love, And from your love I have a warranty To unburden all my plots and purposes How to get clear of all the debts I owe. (1.1.137-141)
Bassanio says he's sharing with Antonio because they're friends, but he makes explicit that he owes Antonio the most in "money and love." (It turns out that Antonio has been very generous with Bassanio, who has a hard time keeping his finances in order.) This is our first hint that friendship might mean a different thing for Bassanio than it does for Antonio. Bassanio might just be working on Antonio's affection in order to keep his purse strings open.
Act 1, Scene 3
ANTONIO I am as like to call thee so again, To spit on thee again, to spurn thee, too. If thou wilt lend this money, lend it not As to thy friends, for when did friendship take A breed for barren metal of his friend? (1.3.140-144)
Okay, we get it. Antonio will never be friends with Shylock because 1) Shylock is a Jew and 2) Shylock charges interest on his loans, which Antonio thinks is wrong. Check out the themes of "Race" and "Wealth" for more thoughts on all this.
BASSANIO. You shall not seal to such a bond for me! I'll rather dwell in my necessity. (1.3.166-167)
Hmm. Bassanio protests against Antonio's offer to put up a pound of flesh to secure his loan with Shylock, but he goes ahead and lets his BFF take the risk anyway. Seems like Bassanio is kind of a user, don't you think?
Act 2, Scene 8
SALERIO A kinder gentleman treads not the earth. I saw Bassanio and Antonio part. Bassanio told him he would make some speed Of his return. He answered "Do not so. Slubber not business for my sake, Bassanio, But stay the very ripping of the time; And for the Jew's bond which he hath of me, Let it not enter in your mind of love. Be merry, and employ your chiefest thoughts To courtship, and such fair ostents of love As shall conveniently become you there." And even there, his eye being big with tears, Turning his face, he put his hand behind him, And with affection wondrous sensible He wrung Bassanio's hand—and so they parted. SOLANIO I think he only loves the world for him. (2.8.37-52)
Again, Antonio's friendship for Bassanio seems boundless. Even now, he's risking his life to deliver his dear friend into the hand of another. It's certain that Portia will turn Bassanio's attention away from Antonio. Antonio is actually being self-sacrificing here, in the "if you love something, let it go" fashion. It seems Bassanio is Antonio's whole world. It's a lot easier to appreciate the nobility of Antonio's sacrifice for Bassanio when he isn't crying about it or busy pointing out that he deserves thanks for it.
Act 3, Scene 2
[BASSANIO reads] Sweet Bassanio, my ships have all miscarried, my creditors grow cruel, my estate is very low, my bond to the Jew is forfeit, and since, in paying it, it is impossible I should live, all debts are cleared between you and I, if I might but see you at my death. Notwithstanding, use your pleasure; if your love do not persuade you to come, let not my letter. (3.2.328-334)
It seems that Antonio is testing Bassanio's love here, basically pitting his love for Antonio against his new love for Portia. Antonio is making a great sacrifice and wants some credit for it, especially if it will make him appear more noble and committed to Bassanio than Portia is.
PORTIA There are some shrewd contents in yond same paper That steals the color from Bassanio's cheek. Some dear friend dead, else nothing in the world Could turn so much the constitution Of any constant man. (3.2.252-257)
Portia's love is going to be in competition with Antonio's friendship. Still, this thought shows that Portia understands the importance of a bosom buddy. She knows she's not the only one in Bassanio's life, even if she is going to be his wife.
Act 3, Scene 4
PORTIA I never did repent for doing good, Nor shall not now; for in companions That do converse and waste the time together, Whose souls do bear an equal yoke of love, There must be needs a like proportion Of lineaments, of manners, and of spirit; Which makes me think that this Antonio, Being the bosom lover of my lord, Must needs be like my lord. (3.4.10-17)
Portia recognizes the depth of the friendship between Antonio and Bassanio. Rather than resent it, she inserts herself into the situation. She won't fight Antonio; she'll actually help him. In the process, Antonio will go from being a competitor to being in her debt. What's more, Portia will come off as benevolent and magnanimous.
Act 4, Scene 1
ANTONIO My Lord Bassanio, let him have the ring. Let his deservings and my love withal Be valued 'gainst your wife's commandment. (4.1.467-469)
Here Antonio convinces his BFF to give "Balthazar" Portia's ring. Not knowing that Portia has just saved his backside, Antonio still insists that his friendship be valued over her love. It's like he's jockeying with her for the primary spot in Bassanio's heart. Seriously, he just nagged Bassanio into giving up the equivalent of his wedding ring!
But this completely backfires for Antonio, because Portia later confronts her husband about giving up the love token and guilt-trips him into being a better husband. You can read more about this ring business in "Symbolism, Imagery, Allegory."
BASSANIO Antonio, I am married to a wife Which is as dear to me as life itself, But life itself, my wife, and all the world, Are not with me esteemed above thy life. I would lose all, ay, sacrifice them all Here to this devil, to deliver you. PORTIA [aside] Your wife would give you little thanks for that If she were by, to hear you make the offer. (4.1.294-301)
Bassanio seems to choose friendship over love here. Maybe it's because he thinks his friend is about to die, or maybe it's because he just married for money. Either way, Portia (disguised here as Balthazar) knows exactly where she stands, but she resolves to do something about it. Keep reading...