Why are you a Muslim?

A Muslim asked the following question on an Islamic site (islamweb.net):
I had a debate with a Christian man and he asked me ‘why are you a Muslim?’, and ‘what did you gain from Islam?’
Please give me a decisive and convincing answer.
The answer:
A Muslim’s belief in his religion must be from a complete rational conviction that cannot be subjected to doubt, because Islam is not simply a blind imitation like the case of some religions which says (sic) to its followers: ‘close your eyes and follow me’. Indeed Islam gave its followers the tranquillity of the heart, inner peace, and a rational conviction that it is the true religion from Allaah which falsehood cannot approach from before it or from behind it.

Leaving aside the depressing fact that this Muslim is incapable of explaining for himself why he has devoted his life to worshiping a deity who promises to torture the vast majority of humanity* (for no other reason than they have failed to recognise that He is "the most merciful of all who are merciful"), the immam's answer is shocking in its oxymoronic duplicity.

Belief must come, he says, from a "rational conviction that cannot be subjected to doubt". There in a nut-shell is all that is hateful in religion, and in Islam in particular: the arrogance that comes from utter certainty that your god is better than anyone else's, the denial of intellectual inquiry, the pretence of logic and rationality and the ever-present implied threat. 

The "explanation" continues by enumerating the reasons why Muslims are "convinced and content with their religion"

The Muslims are convinced and content with their religion because of the following:
1-    It is the religion of Allaah to which all the Prophets of Allaah successively called, starting from the father of humanity –Prophet Aadam  may  Allaah  exalt  his  mention –all the way until the last Prophet, Muhammad  sallallaahu  `alayhi  wa  sallam ( may  Allaah exalt his mention ) . This was after the human mind became mature from the succession of Prophets who were sent to the people with the same call.

2-    This great religion corresponds to the Fitrah (natural disposition upon which Allaah created mankind) of the human being. Islam fulfils both man’s intellectual and material needs. This religion also harmonizes with his mind in regard to his belief, acts of worship, morals, dealings, and rulings in every field.  

3-    This religion only brings what can be conceived and accepted by the sane mind. It [religion] never brings something that is judged by the mind to be impossible to achieve, contrarily to other religions which are full of falsehood, superstitions, illusions and nonsense.

Don't you just love the way that this immam accuses"other religions" of containing "falsehood, superstitions, illusions and nonsense"? Let's not forget that this poor Muslim is asked to accept, inter alia, that desert sprites made of smokeless fire exist (although we can't see them because they are invisible), that the devil resides in your nostrils and you must therefore clean your nose every morning, that Heaven consists of a bachinalean orgy where men get to endlessly shag 90 foot magically rejuvenating virgins whilst drinking magic wine that never gives you a hang-over, that Adam and Eve and Noah and Jonah and the whale REALLY existed, that hell is a place where the fires are eight times hotter than fire on earth, and that God turned some Jews into pigs and monkeys.

How dare this old fool accuse anyone of believing nonsense when he follows the dictates of such a puerile fantasy.

*there are 2 billion Muslims out of a global population of 7 billion. Non-Muslims are destined for Hell, according to Islam, where Allah, in his divine wisdom and mercy has devised unspeakable torments which he will inflict on everyone for an eternity.