Ima play Devil's Advocate. Assuming that you're talking about the Christian god, before you say that we can't know anything about god, first, let me ask,
what is a god? Many believers say god is love or another abstract emotion. They title him as a creator but I can title myself a mother but that doesn't make me a mother. So what is a god?
1. Your experience was real and was from God/wasn't a hallucination.
We all have experiences that aren't "proven" my evidence. We assume experiences are real because of a combination of factors. For example, if you believe your mother loves you, you have no concrete evidence that she does. You are not her. Yet, how she behaves and what she says (for sake of point) makes you believe she cares about you regardless if it is true or not.
Have you ever felt, from out of no where, you are grateful to be alive? Or a moment that you smile and just are happy where you are now?
If so, that feeling wasn't from anything external. What you felt was a combination of emotions that you interpret as a good feeling versus a bad one.
God is the same way. Some people experience god and they turn away because of what he represents. Others draw closer to the experience and find good things that god represents. It depends on how one sees themselves, their lives, and their need for something greater. All of these desires, experiences, and emotions exist. They can be proven.
2. You interpreted your experience correctly.
Which leads me to interpreting god correctly. We have so many definitions of god from inner consciousness to an entity; both, of which, are confusing to me. But if you take your mind from the Bible and see god as an experience-because that is how people talk about him is via their experiences-you have to think by
whose criteria are these experiences incorrect?
I feel Catholicism is the correct "version" of christianity; and, one needs the sacraments of christ in order to be christian. I know this by experience, biblical study, and christian history. If you were to say my experiences aren't true, by whose or what criteria are you going by and is that criteria based your experiences and study?
Wouldn't it be better to judge whether our experiences are real on the criteria we use since religion isn't math to where we can verify facts in a universal matter?
If I want to know that jesus is god, I'd get probably hundred different types of answers. When I read the bible, jesus is not god. Since I am not christian, whose criteria and interpretation of truth should I go by, what I read or what a christian reads? What basis do I find as an outsider what is true and what is false?
3. It wasn't the result of an alternative explanation such as aliens running an experiment on you.
4. God wasn't lying to you or trying to deceive you.
This sounds like from many who were indoctrinated. Many believers don't blame god for lying or deceiving them. They blame satan.
5. Its not a trick from the devil.
On that note, the devil or satan is a personification of our temptations. Try replacing temptation or sin for every where it says satan or devil in scripture.
Temptation exists in all of us. Aka. The devil exists. Yes, temptation can trick us if we fall into it.
Obviously there are probably other problems that have to do with the fallibility of humans. So we really can't use revelation to find anything about God. The same list could also apply to revelations in a holy books except that new problems arise because we have to make assumptions about the mental health and truthfulness of those writers or the fact that it isn't just an exaggerated legend.
Here's another place where your argument falls short. God exist because of the fallibility of humans. If we were all perfect, would there be a god?
It does seem odd, though, to trust people back then before we trust people today as if people back when are more "spiritual" than people today. I think it's because today we are neck and neck with life as
it really is. However, we can't go back in time to experience life then; so, it's hard to prove it either way.
SO what other methods could we use? It couldnt be science since science has no way of investigating God's mind as far as we can tell. It couldn't be from the nature of the universe since we have no way of knowing how or what God would convey through the nature of the universe. It couldn't be through our moral conscience because human moral conscience is probably just a by product of human evolution and can often be extremely erratic or questionable.
The science of psychology, theology, history, cultural anthropology, geology, and physiology explains what we know about the "god experience."
Psychology tells us how god is shaped by our needs for an other or to be fulfilled in whatever way.
Theology explores how religion plays a part in how we defined what fulfills us.
History is very important to many humans as we look back to our origins to define who we are in the present and predict where we may go in the future.
Cultural anthropology shows god because our religions or worldviews are shaped by our culture, language, and environment. This helps us make sense of the world, life, death, and our place in it.
Geology (and all the environmental -ologies) shows that we are taken care of by the earth, planets, and universe as a whole. It gives us a sense of "we are taken care of" however we define or phrase it. By this physical confirmation, everything else falls into place.
Physiology is another cornerstone of how we feel physically (the actual energy/god) when we are fulfilled and psychology is responsible for interpreting whether those experiences come from god, our culture (and the study of it) defines our experiences so our interpretations reflect how we live with ourselves, others, and our environment.
Ultimately, we're left with no way we can reliably know anything about God, which makes me wonder how anyone can think that they reasonably know anything in God's mind. Therefore, I see no reason why everyone isn't just an agnostic, or at the very least an agnostic deist who thinks God exists but doesn't know his mind or his role in the world.
How do you know god, learn about yourself-the questions you ask (what is my purpose? How do I want to live? Whatever comes to mind) Delve into the psychology of your brain.
It doesn't hurt to study theology and the patterns of religions and how they try to answer these questions either by belief and/or practice.
On that note, studying history in general can give you a non-bias sense of how what we believe and practice is not isolated but actual part of history. With that said, christianity is just a part of history as buddhism and every other religion. Jesus isn't special.
Cultural anthropology is a nice subject. However, best way is to actually travel and talk with people of other religious and cultural backgrounds you may not be accustomed to.
Geology tells us everything is forming, creating, and forming. It shows heat or energy is one of the cornerstones of this process; and, if "god" created the earth, god is energy nothing more.
Physiology-don't under estimate the ol' gut feeling. You may say gut but others say it's god. Look outside the box and associate the lingo with the science, history, and culture behind it.