Source: Sarah Broadie, "The Sophists and Socrates," The Cambridge Companion to Greek and Roman Philosophy, ed. David Sedley (Cambridge: Cambridge University Press, 2003) 73-97.
I don't know this chapter cold, so there will be some gaps in this. High school and college students who are searching the web to research for a paper: Don't use this post!
From what I gathered, the Sophists did not believe in morality and justice, and they treated the gods as mere human constructs. Some of what I read about the Sophists reminded me of Kant, in that they viewed reality as something we construct with our minds (or something like that). Socrates, by contrast, believed in morality and truth, and he maintained that people harm themselves when they are unjust.
This struggle reminds me of things I've encountered this week. I get mad at God a lot, but, if God does not exist, what hope do we have? All we've got is a loveless universe. Atheists may respond that we should look to humanity, but I don't have much faith in people. Sure, they can do good, but they are also cliquish, judgmental, selfish, and cruel. At the same time, I agree with what Mary Alice Young said on an episode of Desperate Housewives (from its second season): it's hard to distinguish between good guys and bad guys, since we all possess within us tendencies for goodness and cruelty.
In the sermon I heard today at mass, the priest was saying it's wrong to live as if there's no God. In a sense, that's true. The Sophists focused on people advancing themselves through manipulation and rhetoric. That's the way many people are: self-seeking. We need a moral structure--a system of love and justice that can inspire us. At the same time, I don't think atheists are necessarily immoral. Justice helps society and individuals. I can understand why even a complete secularist would support laws that uphold justice and righteousness.
The priest also referred to people who become worn out with sin. That caught my attention. At times, Christianity strikes me as too strict, with its commands against lust and sex outside of marriage. But doing that too much can lead to feelings of bankruptcy and meaningless. It's like I used to feel after being drunk: thirsty, inwardly empty, etc.
In any case, these are just my thoughts. Some may disagree with me, but it's how I feel right now.