People of other faiths will say things like, "I just *know* this is the truth. I really, really know it. I'm so certain about it without a doubt." A friend of mine and I were talking to a Mormon girl at University once and after talking to her about the rational reasons why Islam is the truth, and some scientific miracles, she asked us how we know Islam is the truth. It really confused me because I had just explained to her some pretty obvious reasons, but she said - very genuinely, "but do you guys have faith? I mean for me I know mormonism is true because I have this burning feeling in my heart. I asked God to guide me to the truth and I knew this was it" (something along those lines).. She very genuinely believed that the truth about God was acquired by 'a burning feeling in your heart'!
In any case, why do people of other faiths have such seemingly certain knowledge that their religion is true without, or even despite of, evidence?
I can't claim to know what people experience in their hearts, however.. you can actually have religious-like moments of conviction about something completely unreligious, and you can even have them frequently - and about really, really shallow things. I remember having them with music!!
You see when the love of something - anything at all -enters the very depths of your heart and your heart becomes consumed with it, whenever this love is fulfilled - when it reaches a peak - you have a moment of pure ecstasy. And in this moment of pure ecstasy, for a split second and sometimes for much longer, you confuse emotion with knowledge, ecstasy with certainty, and something inside you says, "this is *it*. This is where I should be in life. This is what life is about" and it actually feels like *knowledge*, like you *know* this is the truth. Either it is a misfiring of neurons in your brain, or the shaytan making use of your foolishness or your nafs - whatever it is. And the thing is is that a person of this dunya can have these moments of almost spiritual conviction about something really awfully stupid.. I remember having those kinds of moments with friends - after having an amazingly good time with friends, after having a really good laugh in a really fun outing, I would get this (incredible as it seems to me now) moment of certainty, conviction, that this is absolutely what I should be doing. You know the saying, "feels so right that it can't be wrong"? That's exactly what it is. You feel so good that you believe, against all reason, that it's objectively true that this is *right* - and the ridiculous thing is an atheist can feel this way too.
And you know when people get this feeling most frequently in contemporary culture? When they're in love. Being in love very perfectly captures this because the heart very quickly becomes consumed with the one they are in love with - much more strongly than friends and music, etc. - and so you will find that they are very easily moved to moments of extreme happiness, and so they are frequently thinking, "this is so *right*!" And the lyrics of songs is full of people firmly believing that somehow it's objectively correct for them to be with this person - as close as you get to religious conviction. And the amazing thing is that there is evidence to this straight from the horse's mouth. An atheist once complained on youtube that a Christian told them that believing in God is like falling in love, 'you just know'. !!!
Funny thing is that one of these moments was one of the things that made me realize music is haram. I was listening to beethoven or some other type of music (just pure music with no lyrics) and it was so beautiful that my heart soared and in that moment I thought, "this is *it*, this is life" And then I was like, wait what?! No it's not! I know for a fact that this is not *it*.. and if it was *it* then surely Allah would have made music a very important part of His deen.. I reasoned, in that moment, that nothing should be able to move my heart so strongly if it is not what I should actually be doing in life - if it is not my reason for existence.
So now that we know what's *not* moments of conviction, let's compare and contrast to this deen - to the Truth from Allah Azza wa Jall. Now, a skeptic will argue that we shouldn't make exceptions for our deen (and there's a term they use but I can't remember) and so if it is false for other religions then it is false for us too. Firstly, I actually get much fewer moments of pure ecstasy than I did in my days of jahiliyya, and I suppose that makes sense because if your heart is consumed by the love of Allah or at least something related to this deen, then it is much more difficult to fulfill that love - because the fulfillment of the love of this deen comes with effort and hard work, except in those times where Allah graciously bestows moments of love upon you. Secondly, I don't think Allah allows ingenuine feelings of love or religious fervour but I might be wrong. In any case, let's for the sake of argument accept that to be the case that similar moments for a Muslim can be explained away by too much happiness.
There is however a second type of moment, feeling, of religious conviction that exists *only* in Islam - and that is when the feeling of joy and happiness actually comes *after*, and because of, a moment of certainty - of knowledge. You see in the moments of conviction caused by this dunya, the sense of awe, wonder, love, happiness *(mis)causes* a feeling of certainty. But there is in Islam the opposite - in a moment when the ayaat of Allah, the signs of Allah, are so evident and so strong, for a moment it is as if the veil from your heart is lifted and you are seeing the unseen, and you know in your *mind* first that this is the truth, and then your heart is so pleased with it that you get a moment of pure joy that is unlike the joy of the dunya because it is a blessing from Allah.
And the awesome thing is that it's not necessary for it to be accompanied with a feeling of ecstacy - our knowledge of Allah and this deen cannot be simulated by an adrenaline rush or smoking weed and having a high, it is the most firm knowledge that a human can reach. I used to get these moments of certainty when studying Biology for example. You are so filled with awe at the creation of Allah - the absolute genius of His creation, that you know without a doubt, without even a shadow of a doubt, that there is a Creator. You see your *mind* knows it, and then your heart feels it. Or sometimes you can get these moments of certainty with signs in your own life. That's the difference between Islam and other religions - you can actually share that truth with other people, even if it is something that happened in your own life. And it's actually happened with me with something that's recently happened in my life - such an incredibly improbable series of events that led to an outcome, that even when I shared them with other people they thought, "ah yes I see what you mean".. And I'm sure there are things in every muslim's life that are the same.
Alhamdulillah for Islam