Assuming you not an African bushman from a few centuries ago you can know that from the bible. Let me fill in some context. The fact that the bible is the best selling, most scrutinized, and most cherished book in human history plus that it covers the most profound subjects anyone can possibly think of it certainly deserves investigation. No one can get through the book of numbers of kings with a struggle but the Gospels are easy reading. In there you would find that verse plus many others saying the same things. Isn't it at least worth a serious shot. That is what I did, one day I said "that's it I am going to get to the bottom of this religion thing", expecting to reach a negative verdict. To my surprise I reached the opposite. Anything in that description beyond your capacity?
You mistake me. I have read the Bible -- more than most Christians I know, actually, because I've been a huge reader all of my life. And I have written on it, as well -- often receiving (as in University) high praise for the quality of my exegesis -- although my exegesis did not and does not lead to the same place as that of many others.
I do not know how you read, and what you include or ignore in forming your overall opinion of what you've read. In my case, it is and has always been that the Bible is not coherent -- rather the reverse in many ways. And I cannot help but observe that much of the overall message of the Gospels and the rest of the NT are not followed particularly well be most people who claim to be Christian. For example, in spite of being told "take no thought for the morrow," everybody is constantly worrying about it, and in spite of being warned that it is damned near impossible for a rich man to get into heaven, far too many are striving far too hard to be just that -- rich. And the NT is extremely clear about one thing: the Parousia was imminent -- so much so that there really was no point in even getting married, unless you couldn't contain yourself.
(And by the way, I've also read the apologetics that try to explain all that away, and find them generally specious and self-serving.)
Its like (only far stronger) like being in love. If you never have been you question its existence, once having been you know it.
The same can be said of infatuation, which is far too often mistaken for love. It is, unfortunately, based to much on surface matter and not enough depth.
You are again describing something other than Christianity then condemning Christianity for it. We are only responsible for the revelation we have been exposed to. I am not an expert on this issue. I recommend William Craig's book on the problem of the unevangelised. However I will give one example. The Jews were required to have faith in a future messiah, just the same as the Christian is to have in a past messiah. This is referred to as progressive revelation.
Craig is the worst of the lying apologists -- one that I would accuse of doing a lot more eisegesis than exegesis. ("Reading into" rather than "reading out of.") No doubt he believes himself to be totally honest. I unfortunately do not.
That being said I am perfectly aware that we are all strongly emotionally motivated to accept what confirms our existing beliefs, and reject what contradicts them. I'm the same, no doubt. But I
think that I work very hard to spot my cognitive dissonances, and to deal with them analytically.
And as a result, it is my
considered belief that most revelation is in fact largely wishful thinking mixed with fundamental errors in reasoning, largely brought about by our own biases.