Socrates asks himself before the jury why he should have been so willing to pursue his line of philosophical inquiry if the resentment it has earned him has put his life in danger. He answers his own question, saying that when performing an action, the only relevant question to concern oneself with is whether one is acting justly or not. Considerations of life and death are selfish and unimportant next to considerations of justice. Since his calling to the philosophical life came from no lesser power than Apollo himself, Socrates should be even less willing to abandon his post as a seeker of truth than a good soldier would be to abandon his post in battle.
Socrates' wisdom comes from acknowledging that he does not know what he does not know, and his acknowledgment that he does not know what awaits him in the afterlife leads him not to fear it. A fear of death, then, is just another kind of false wisdom, of claiming to know the unknowable. On the other hand, he knows for certain that it would be wrong to disobey the will of Apollo and stop philosophizing, so he would be foolish to do what he knows is wrong for fear of an unknown quantity. Socrates goes further to suggest that if the court were to acquit him only on the condition that he give up philosophizing, he would refuse their offer, choosing to die rather than to abandon his duty to Apollo. His priorities are clear: wealth and honor are trifling concerns next to the pursuit of truth and the perfecting of the soul. This is the message he preaches to the youth of Athens, and unless such preaching corrupts them, he is innocent of the charges laid against him.
Putting an innocent man to death is far worse, and thus far more to be feared, than dying oneself, according to Socrates, and so really it is the jury, and not Socrates himself, that is in grave danger. In doing what he does, Socrates claims he is doing Athens a great favor, and he will not be easy to replace. In a famous passage, he likens himself to a gadfly and the state to a large, lazy thoroughbred horse. He is constantly buzzing about, waking his fellow citizens out of their sleep. Though his presence may be irritating, the state will be more awake and productive thanks to his services.
Unlike most Athenian men, Socrates has mostly kept aloof from politics and public affairs, preferring to interact with people on an individual level. He explains that this behavior results from a supernatural sign, an inner voice which comes to him and dissuades him from getting involved. This, he claims, is the only reason he has lived to the ripe old age of seventy, since no man who acts in opposition to the state, however justly, can survive for long. To prove his point, he refers to two occasions on which he opposed the authorities in the name of justice; in both cases, he nearly died from his bravery.
While in his more mature works, Plato asserts all sorts of positive doctrines (the most famous of which was his theory of forms), it is highly debatable whether Socrates advances any positive theses at all. On one hand, he quite explicitly claims that he knows nothing, and that his wisdom lies in his acknowledgment of that fact. On the other hand, there do seem to be some ethical principles that radically inform all of Socrates' thinking. For instance, he is famous for stressing the importance of knowing oneself and for asserting that no one ever knowingly and intentionally does evil rather than good.
In this section of the text, these ethical principles come into play in force as Socrates passionately defends the justice of the philosophical life. As he has already stated, his role as a philosopher is to question people regarding their own supposed knowledge and to show them that their wisdom extends only as far as their acceptance of their ignorance. In this respect, he is helping people gain wisdom (his kind of wisdom, that is) and overcome ignorance. Socrates implicitly associates wisdom with goodness and ignorance with evil, in accordance with his principle that no one knowingly does evil. If we are all uniquely wise, we cannot possibly do evil, since evil deeds are the result of ignorance above all else. Thus, leading the philosophical life is a supreme moral duty, as it is the most direct way of overcoming evil.
A proper treatment of the Socratic claim that no one knowingly does evil could be a very long discussion; we will only touch on it briefly. First, to clarify, Socrates does not mean to suggest that no one ever commits an evil act out of hatred or selfishness. Rather, he wishes to suggest that hatred, selfishness, and any other source of evil action can ultimately be traced back to ignorance. For Socrates, hatred between people is the result of misunderstanding or miscommunication, and selfishness is the result of deficient self-knowledge. If we knew ourselves and others fully, and had a full understanding of the facts at hand, we would never commit an evil act.
Another question regarding the Socratic claim is how far we can take it to be a claim at all. Interestingly, Socrates never seems to directly assert this claim, and he certainly never argues for it. Usually, he just implicitly treats it as though it were self-evident. If it is not a positive claim that can be argued for, Socrates is not violating his claim that he has no positive knowledge in any specialized field. But if it is not a positive claim, what sort of claim is it? Perhaps we could argue that it is an intuition, one that has no evidential basis. Alternatively, we could read it as an empty claim, asserting nothing more than the fact that if we knew everything, we would know what was best for ourselves. There is no easy answer to this question that presents itself to us in the text.
For a man such as Socrates, who claims to be so committed to improving the state and its citizenry, it would strike the jury as odd that he places so little emphasis on public affairs. This, he explains, is the advice of his supernatural sign, the voice in his head that warns him against such activities. This sign could be taken to be one of the supernatural things that Socrates believes in, which he used as evidence of his belief in gods during his earlier cross-examination of Meletus. Interestingly, though Socrates is persists in saying that this voice is of supernatural origin, he nowhere suggests that it has to be a god, in spite of his earlier assumption that all supernatural things are either gods or children of gods.
In any case, the "sign" is right: Socrates would not last long in public affairs. His present trial is just one of many cases in Athenian history where justice was unfairly suspended when the safety of the state was thought to be at stake. Socrates' emphasis is on the ethical life as expressed on the personal level and through self-knowledge. In Socrates' view, the health and prosperity of the state would follow if every one of the citizens were wise and virtuous, but no set of laws can ensure such health and prosperity if the citizens act unjustly. These considerations were especially pertinent following the Peloponnesian War, as Athens fell into decline.
This is arguably one of Socrates' most famous quotes, and in fact, living the examined life was the main cause of him sippin' on a killer cocktail. But, what does he mean? Why does he think that death is favorable option to living an unexamined life? What does the examined (or conversely, the unexamined) life look like? Another way to think about this is "Why does Socrates so willingly accept his fate?". Just food for thought.