There is an assumption in some circles that all rational people should be atheists. That all who profess philosophy should be is even more widely held. But I can't bring myself to that anti-credo.
To deny the existence of a thing (or a being), I have to be able to understand what that thing is, to have some fairly clear idea of what it would be for it to exist. I have a fairly good idea of what it would be for unicorns to exist. I understand what they are supposed to be like, what their biology looks like, their strange predilection for virgins, and all the rest. Similarly, I have a good idea what it would be for Zeus to exist. I know what his story is supposed to be, I know how he is supposed to have originated, I know his strengths and weaknesses, I know of his marital strife, his lusts.
So, I know what I am saying in denying the existence of unicorns or Zeus. And, I know what I would be saying in denying that Jesus existed--I think he did--or in denying that Muhammad received revelations from Gabriel or that Joseph Smith translated any golden plates.
But, I don't know what I would be denying the existence of God, full stop. I don't think atheism is, after all, just denying one more god in addition to all the others I freely deny.
I'm not just being precious here. I don't know what it means to say there is a Being who is the ground of all being. I don't know what it means to say that there is a Being that is outside of and utterly different to the universe, yet is the cause of the universe. I don't know what it is to say that God is both good and tolerant of all the suffering in the world--after all, His ways are mysterious.
There is a long tradition in the monotheistic religions of saying that what we say of God is said by analogy or metaphorically or, at least, predicated of God in a different sense to the secondary sense in which we predicate goodness or knowledge or anything else of beings in the world--here is the realm of the via negativa, the mystics, even Aquinas. This is just to say that we cannot understand God.
But saying that is tantamount to saying the claims of theism, taken literally, are a kind of nonsense--Unsinn. I don't mean that in a necessarily pejorative sense. Nonsense can be good, nonsense can be useful, nonsense can be evocative. We may need nonsense. Perhaps art is, in some ways, nonsense. But nonsense can't be true.
And, it can't be false, either. A negation sign doesn't make nonsense into sense.