The point that Socrates makes is that, in the same way, no person can believe in spiritual and divine agencies without also believing in spirits or demigods. In this way, the accuser, Meletus, contradicts himself by saying that Socrates teaches and believes in divine agencies without in fact believing in the gods themselves. Socrates shows the illogical nature of this accusation by making the point that one cannot believe in a divine manifestation without also believing in the god behind it. Indeed, it would be as absurd as believing that mules exist without believing in the horses and donkeys that created them. Socrates here correctly accuses Meletus that he in fact has nothing to accuse the philosopher of, and proves himself to be a believer in the religion of the time.

4. Socrates' reaction to his sentence is interesting, while also being in keeping with the philosopher's general views and bearing during his life. He completely accepts the sentence, even while he knows the officials who made the accusations and brought the sentence are corrupt. Rather than lashing out against them, he chooses a peaceful departure. This indicates a number of basic assumptions that Socrates makes about life and death.

Socrates does not assume an inherent "truth" about death. He acknowledges that it can be either complete annihilation or the culmination of the soul in life after death. What he does however assume is that it will probably be good, regardless of which occurs when he dies. He explicates this by addressing...

This type of sleep will be so deep and undisturbed that not even dreams can intrude upon it. After the turmoil of life, living, and indeed normal sleep, the philosopher believes that death will be an "unspeakable gain." If these were to be true, then death would be like a single night of absolutely undisturbed sleep.
On the other hand, death as the migration of the soul would also be a great good. In the spiritual world, all judgments and personalities are perfect. They are not weighed down by the petty personality problems of living human beings. Instead, the soul will meet the "true judges." The assumption here is that, if death meant continued life for the soul, it would be a life of perfection rather than the imperfections experienced in life. Here Socrates suggests that his current judges are much more corrupt than would be his judges after death. In such a case, Socrates is looking forward to meet the great names of mythology, literature, and culture. To be able to have a conversation with them would be a great reward to the philosopher. In this way, Socrates assumes that, whatever happens after death, it will invariable be good.

Bibliography

Plato. Apology - translated by Benjamin Jowett. The Internet Classics Archive. http://classics.mit.edu/Plato/apology.html

Plato. Euthyphro - translated by Benjamin Jowett. The Internet Classics Archive http://classics.mit.edu/Plato/euthyfro.html