Whatever that you use as proof that your own religion is the one true religion disproves your claims about your own religion along with any other religion that could ever exist.
According to the Quran, Islam is the only true theistic religion. The Quran mentions that Islam is made for all time, and that Islam in and of itself renders all other previous divine religious texts and theistic religions obsolete. According to the Quran, all non-Muslims are considered infidels and are to be tortured by God in hell for eternity, and they will never be forgiven or taken out of this eternal torture in hell for any reason or at any point in time later on, whether these non-Muslims are Jews, Christians, following or believing in any religion other than Islam, agnostic, or atheists. According to Islam, all of the above or all of these categories mentioned earlier are sentenced to torture in hell for eternity alike, without redemption, without the luxury of any further appeal, and without this ever being subject to reconsideration or change by God for any reason, and whether those non-Muslims were against Islam in any way, opposed Islam by any degree, were in favor of Islam, liked Islam and Muslims and treated them nicely, never harmed or threatened the existence of Islam itself or the spread of Islam, or never worsened or attacked the image of Islam or affected how much Islam appeals to non-Muslims, and even if these non-Muslims never harmed, endangered, or threatened any Muslim, and even if these non-Muslims totally believe in god beyond the shadow of a doubt. A lot of people who misrepresent or misinterpret Islam and who claim to be religious moderates whether Muslim moderates or Non-Muslim moderate religious believers claim that this is not indicated in Islam and should be considered as a misinterpretation or misrepresentation of the Quran, or only a radical or an extremist version of Islam, but the evidence of all of the above being factual is abundant and more than enough in the Quran itself. It is literally all over the place in the Quran, without being indirect or subject to being considered metaphoric, or having the potential to be understood otherwise or in any other way. And there’s nothing in the hadith that indicates otherwise or contradicts with any of the above.
It is still, however, possible to experience whatever feelings, spirituality, and faith as a result of practicing religious prayer despite not being Muslim. Why would God give those feelings and effects of religious prayer to someone who he will later condemn to an eternity of hell?
These spiritual states should be exclusive to Muslims in this case. Only Muslims should be able to have those religious or spiritual experiences. Especially those who lead you to assume certainty about Islam being the only one true religion from God there is or currently present or available to humanity.
Why would any Christian feel bad in a special way after committing anything that is considered to be sinful, immoral, bad, forbidden, or wrong in Christianity, that is identical to how bad Muslims feel for example because of or after committing something that is considered to be of the same magnitude of how sinful, immoral, bad, forbidden, or wrong it is according to their own religion Islam, while feel virtually nothing after committing sins or crimes that are considered insanely sinful and an atrocity according to the standards set by Islam, but are not considered to be forbidden, bad, immoral, sinful, or wrong under Christianity. For example, drinking wine or lending money with interest. Simultaneously, both religions claim that the only reason you don’t feel bad after sin is because you don’t believe in God. They both seem to have no problem with considering your inability to feel bad after committing any religious sin to be due to you being an infidel or a religious non-believer, although according to Islam and Christianity, both members of the other religion and those who don’t believe in either Christianity or Islam are equally infidel or non-believers who will be sentenced to hell for eternity by God. To them, it doesn’t matter where you came from. All that matters is whether you believe in their own one true religion or not. Treatment in the first life may differ, but punishment in the afterlife would be virtually the same in both cases of Christianity and Islam. And for some reason you still believe that your certainty about the subject matter of whether or not there is a God, and that this God is certainly your own religion’s version of God, through relying solely on how certain and how strongly you feel about what you believe is somehow still reliable evidence for such a colossal claim.
Even Muslims who believe that something is not a sin do not feel bad when they do or commit it. Whilst other Muslims who believe that this same thing is a sin, (because of their differences in interpretation, understanding, or views of what is to be considered right or wrong in their own version of religion, in this instance, Islam), feel bad and guilty when they do this same thing or commit this same act. And if these same Muslims doubt the existence of God or question any of his teachings, commandments, or will concerning anything that happens in this world, they might end up feeling way worse than they could ever feel because of or after doing or committing anything that is forbidden under Islam that is considered to be of less magnitude in terms of sin than the sin of infidelity or disbelief in god, including how guilty they feel afterwards all the time because of what they did.
Islam for example, claims that all such negative feelings including the guilt and remorse, are all some form of punishment by god to the sinful.
If that was true then any Christian would never feel bad when they do something they believe to be forbidden or considered to be sinful according to Christianity, just because they are not Muslim, and thus are lost or doomed anyway no matter what they do or don’t do.
What about feeling good after they, despite being Christian, repent? How could any Christian feel good after they repent, if the claims made by Islam were true?
How about the way a Christian feels after believing that God has answered their prayers?
Moreover, Christians pray and see, or at least think, that their prayers have been answered by God, despite Islam making the claim that God does not answer prayers from religious non-believers, or from anyone who is not Muslim, no matter how hard they try.
This is impossible to take place unless whatever that makes any Christian believe their prayers have been answered by God is the same that makes any Muslim believe their prayers have been answered by God as well. In other words, a false fixed belief, a delusion.
One need only believe in a supernatural deity residing in the sky that answers prayers and controls everything there is in order to feel any of the above emotional certainties that are perpetually used by religious believers to justify their positions toward religion. After the above demonstration, it should be clear to you that whatever feelings, spiritual or otherwise, including changes in mood, not to mention any form of invisible connection or communication you might have with God is all but a delusion, that only feels true because you profoundly believe in it.
At least the fact that any of these feelings seem to be identical no matter which religion you believe in should indicate that your certainty about your own religion or version of religion to be the one true religion from the one and only true creator of the universe should be questioned, or should at least not remain so intact, not to mention totally nullified. At least your spiritual claims and beliefs shouldn’t remain that certain, or shouldn’t retain that much certainty from now on. And that it is very likely to be based upon something that exists because you were severely indoctrinated at some point in your lifetime prior to no longer feeling the necessity of exercising doubt or skepticism upon anything unless it falls under the category of politics or the government.