Wasn't there a line about good overcoming evil?

In response to my previous post on gay cooties and the Fundie insistence that Christians should avoid gays, a former pastor of my church wrote:

I thought it should be the other way around--that "good morals" might be more powerful than bad company--but then again, who knows where bad company lies?

And that reminds me a good deal of the bible is about how good overcomes evil. So if being gay is evil (which it isn't), it seems certain Fundies don't trust their goodness to overcome it. Then again, since a good deal of what they say is based on violating the 9th commandment, perhaps their good isn't all that good.