Evidence is only one way of justifying a belief in a god or gods. I can think of at least two other things that would rationally justify a belief in the existence of a god or gods: Personal experience with such a being, and the personal testimony/witness from a reliable source.
I believe that evidence is a good ground for why a person can rationally believe in the existence of a god. Note that when I say evidence, I am not saying that it must be a proof. Many times, when an Atheist asks me for the evidence for the existence of God, what they are asking me for is not in fact evidence, but rather, what they are demanding is that I show them proof that God exists. I do not claim to have a proof of God’s existence, in the sense that it would be impossible to refute. I claim to have evidence for the existence of God, which another person may or may not contend and try to explain the evidence away through some other means.
If there is sufficient evidence pointing to the existence of a god, then it is rational for a person to believe in that god, even if that particular god doesn’t happen to exist. (more on the second half of this claim later) This may seem counter-intuitive, but stay with me for a moment.
I find little value in any viewpoint that takes a radically skeptical view of truth, because it is nigh impossible to live out such belief. We cannot function and perform our day to day tasks while living as though we cannot know anything. It is impractical, and completely goes against how we live our lives. I do however see the value such radical skepticism has, in that it allows us to be challenged in our thinking and not just take what we think, or what seems intuitively true for granted.
There are some Atheists out there who don’t claim they have such a radically skeptical view of Truth, but do however say that we shouldn’t live by faith in anything, whether that be religion or otherwise. These Atheists desire to take a large step away from faith, what they see as the basis for religious belief (which in turn they see as a bad thing) and instead claim they want hard evidence for anything they believe. They desire the kind of evidence they claim we get from science. This kind of thinking is not necessarily a radically skeptical view of truth, but it is a strong form of skepticism, which I find untenable. It says that you can’t take anything on faith, and instead must be able to prove it through (mostly empirical) evidence. This is simply a false way of viewing the world. There are multiple things that everyone (even people who do not believe in any religion) take on faith (unless presented with valid reasons for thinking otherwise) everyday.