Unfortunately there are a great many definitions of Faith (a few of which I'm actually ok with). Most arguments about Faith get derailed long before deliberations begin- they get derailed because of a fundamental difference the two people have in their definition of Faith. So I'm going to try to be as specific as possible here and avoid using the generic term "Faith." Instead, I'm going to talk about "contingent belief", "non-contingent belief", and "divinely imparted belief" as proxies for what most people mean when they talk about Faith
Contingent belief is the kind of Faith that I'm OK with. This kind of Faith is really just a different way of talking about weak Bayesian belief (I think its a mistake to call this "Faith" at all, because it seems to me so categorically different from the other types of Faith. But this is the definition some people use- particularly when trying to accuse science of requiring Faith). It is a mental assent to a proposition that you are less than sure about, but it is necessarily beholden to your future experiences. Scientific theories all fit into this category. We're not 100% sure of anything, and if we find sufficient evidence against a theory, we will discard it. Moreover, we have (or ought to have) no emotional attachment to this kind of Faith, and having this Faith is neither virtue nor vice- it is simply applied logic.
Non-contingent belief is that belief which I cannot accept. The problem with non-contingent belief is that it separates our beliefs from reality. We are no longer tied down by experience or reason, but rather let loose to roam the plains of our own desires. To put it another way, if we allow ourselves non-contingent belief, how are we to decide what to believe without evidence? Surely there are a great many possible beliefs that we could hold without offering any defense for them. Why pick Christianity, or Islam, or Buddhism? Why not pick "Jakeism", the religion of Jake, in which I am god and get to decide what is right and wrong according to my own whims?
I want to be clear that I don't think most religions fall into this category- but many do glorify such belief. The intelligent Christian believes because there are good arguments, and he is convinced of the historical accuracy of scripture, and he cannot make sense of life without the meta-ethical framework that Christianity provides. This man may well be wrong, but he is not believing without basing his conclusions on evidence. But when a religion exhorts its followers towards Faith- towards belief without evidence, or worse, belief in the face of evidence- my spider sense starts tingling. We ought not believe anything on this kind of Faith. If we find evidence or experiences that contradict our religious beliefs, we should question our beliefs. Either our beliefs are correct, and we will find good answers to our questions, or our beliefs are incorrect, and we will be one step closer to finding the correct beliefs.
What I want out of my epistemology is to become a more accurate predictor of reality. The only way non-contingent belief could accomplish this is if there were something that was true, but no evidence could be offered up for it. While it is conceivable that such truth exists, consider which is more likely- that someone claiming absolute truth without evidence actually has the truth, or that someone claiming absolute truth without evidence is wrong. Obviously, we expect you to have no evidence if you're wrong. You haven't differentiated yourself from other people claiming truth if you tell us that we need faith to believe you. I don't want arbitrary belief; I want belief based in reality.
But I think the best argument against non-contingent belief is the following: any non-contingent-belief-Faith you have derives from your belief in the Authority of something else (a holy scripture, a prophet, a tradition, etc.) which tells you to have Faith (or at least tells you the truth you ought to have Faith in). Your Faith can never be stronger than your belief in the Authority. Likewise, that belief in the Authority can never be stronger than your belief in whatever it is that gives your Authority-source it's Authority. After peeling back all the layers, there are only two places you can end up: experience, or reason. Your Faith cannot be stronger than your belief in experience and reason, because your Faith derives itself, through layers of abstraction, from this experience and reason. Otherwise, what you have is a floating belief, not tied to any actual observable reality. If your Faith in the Authority is working in a feedback loop with the Authority proclaiming Faith, you need to take a serious look at your belief system, because you would believe it no matter what it said. You believe it simply because you believe it, and for no other reason. You are perpetuating the status quo for the simple reason that you already believe the status quo. And that's why non-contingent belief is such a great evil- because it is inescapable, even when its wrong.
This brings us to divinely imparted belief. I'm not sure what exactly I can say here, other than throwing up my hands and rolling my eyes. Fine. You believe you have divinely imparted belief. You don't need reasons, because you simply *know* something is true that the rest of us don't see. This is like the man who is convinced the world is one big dream of his, and he will be waking up any minute. Nothing you can say, nothing you can do will ever convince him otherwise. Divinely imparted belief is (most often) a veneer placed over a gaping hole in the reasonability of a religion.
Again, I want to be clear that I think divinely imparted belief is totally possible. But you ought to be so suspicious of it that you don't believe it, even if it is true, because you're not the only one claiming this. If other people can be mistaken about the level of certainty they ought to have in the divine origin of their beliefs, why can't you? It seems like hubris to claim that we have divinely imparted belief, which we can be sure of because it was divinely imparted, but your divinely imparted belief is purely psychological (and by the way, you should convert).
Before closing this post, I should note that C.S. Lewis has a definition of Faith that I can totally get behind. He basically says that Faith is the ability to hold on to what you know to be true even when it doesn't seem true at the moment. Certainly mood, circumstance, and chance play a large role in our lives, and can definitely affect what we consider to be reasonable at a given time. If all we require of Faith is that it is a caution against impetuous overcorretive steering, then I'm on board- you shouldn't make big life decisions about what you believe in an instant. But if we're saying Faith can keep us from converting or deconverting long-term, even when we're convinced that the evidence is arrayed against us? I'm not buying it. That's what keeps people trapped in false religion.