I must admit that I only briefly browsed through the posts here, and all are excellent insha'Allah.. I have to however agree strongly with MD Mashud's post.. the best way for you to re-affirm your belief is to go to the deepest darkest corners which will sow doubt and fight it head on with reflection and deep thought...
to be succinct, I don't believe that anyone can sum up for you, why they chose Islam or why they remain Muslims.. and indeed prayer and du3a will help, but I think of them as functioning only in a supporting capacity but not an orderly logical arrangement as to why you chose this religion.. what will you say to your kids someday?
The best way is to truly learn all you can...You'll find many members here who are scientists and some who are even former atheists, who arrive to their conclusions based on the scientific approach.. you just need to filter through the crap and shadowy conclusions that others produce...
Two people can read the same book and reach completely different conclusions.. you may browse through the Muslim evolution thread, before it dernaged into unsubstantiated opinions, and find out exactly from a scientific stance where the flaws lie in the subject of evolution... How even natural selection contradicts some of the readily known and accepted conditions of today's world such as the 14 documented trinucleotide repeat disorders that affect human beings, where the worst traits are not only favored over time, but actually get worst with each generation.. There is always so many holes that no one cares to mention to you, and you'll only know of them through learning, reasoning and never ever accepting anything at face value... You need to understand that those who have made it, thought outside the box and didn't readily accept everything that was dished out to them...
I hope you know that even Einstein was kicked out of school for doing poorly in math.. I don't believe you've ever heard of the teacher that expelled him or why he managed to come up with his best work outside of academia..
Akhi, I am going to be off for Fajr now, but I hope the take home method here, isn't how staunchly someone defends his principles.. but in how well s/he has integrated them with the known world using all subjects at hand..
I wish you the very best insh'Allah, I shall keep you in my prayers...
knowledge is the only way to cast doubt insha'Allah

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