[5:3] Today, I have perfected your religion for you, and have completed My blessing upon you, and chosen Islam as Din (religion and a way of life) for you..
In this article we show that every single non-Islamic religion has a fatal flaw that essentially shows the falsity of that religion. This flaw relates to joining of mutually exclusive and contradictory claims when it comes to God, His Essence and His Attributes. We may concentrate on a certain religion (Christianity for example), but for all non-Islamic religions, the basic premise stands: These religions are claiming mutually exclusive and contradictory claims with respect to God and His Nature, Attributes and Essence. Taken a whole, their claims are invalid and should be rejected by every sane human being.
It is best if we focus on showing how the different non-Muslim ideologies are faulty and flawed as religious systems, rather than slowly comb through the books of our opponents trying to find some or the other piece of truth in their religions. Thus, in the case of the Christian Bible, we will not try to show that the Bible has prophecies showing the truth of Islam, because such a situation is somewhat far-fetched when one considers the totality of the Bible. Rather, what we are trying to show is that the Bible and the Christian religion adopt a series of stances that when taken together show that they do not have any intelligible positions regarding God, and that their religion at the very core is totally inconsistent within itself and should be rejected outright.
Now, one of the matters we commonly hear among the non-Muslims is how their knowledge of "God" is wrapped in mystery, or how "God" does not and cannot conform to our standards of logic and rationale. As Muslims, we indeed do say that full comprehension of God is not possible for any human being to attain. However, what our non-Muslim opponent is advancing by means of his reasoning is not only that "Full knowledge of God is incomprehensible by human beings", but that "no intelligible statement can be made about God at all". We explain this as follows:
What our opponent is positing is that it is possible for there to subsist mutually exclusive attributes - that is, totally contradictory attributes- within God Himself. If we take the matter of God's existence, our opponents are saying that the phrase "God exists" also accepts its opposite "God does not exist" as being true. So for them Existence and Non-Existence can both be true descriptions of His Self, and the position of the atheists who say that "God does not exist" is also potentially true.
The same goes with the statement "there is only One God". Since our opponent cannot make recourse to any logic at all in describing God, then He is saying that the statement "there are multiple Gods" can also be true according to him. So if someone says "there are 20 Supreme Gods", our opponent cannot object, since for him 1= 20 is a potentially correct statement when it comes to describing God and His Essence.
With respect to the statements made in the "Holy Books" of our opponents we have the same issue at work in here, since our opponent holds that truth and falsehood are the same, and that God could reveal and inspire truth as well as falsehood in the bible. Moreover, since for our opponent knowledge is the same as ignorance, then it is possible for his "God" to have inspired some things to be written in the "Holy Books" that were in accordance with God's knowledge, but other things could have also been written in the "Holy Books" which "God" was not fully aware of. Thus, our opponent cannot fall back and say that such-and-such doctrine is true because it is mentioned in the "Holy Books", since in his worldview God transcends rationality, truth is the same as falsehood, and it is possible for both to be mentioned in the "Holy Books" without us human beings being able to differentiate between them at all, even if God supposedly assures that this is the case - because to our opponent, "God" can assure humans of the "truth" of a false statement, or He may not even know whether a statement is true or false so "God" may unknowingly assure us of the truth of a false statement.
So it is clear that our opponent is in a quandary. Even if our opponent says "God is beyond the laws of logic" one would need to use logic itself in order for this proposition to have any meaning. Why? Because the person is making a proposition and is presenting this proposition as being true. That is, they are saying that the statement: "God is beyond the laws of logic" is true and not false, which is based on rational reasoning. If they totally reject rational reasoning, then they cannot even say that the statement "God is beyond the laws of logic" is true and not false, since it could be both true and false at the same time as per their rationale, a rationale which allows fallacies and incongruence with respect to discussions about God.
As another example, the believer in God –even the one who says that rationale has no role to play in understanding God- says that there exists only One Supreme God. This person knows that the phrase "there is no God" is false and not true. This is why he would do his utmost to try to refute the statements of the atheists in this respect, since he acknowledges that most certainly God does exist and His Non-Existence is logically unacceptable and impossible. If he did not take logic into consideration at all, then he and other believers in God would have never written thousands of works refuting atheists, nor spent decades upon decades doing their utmost to show that the arguments of the atheists are false and invalid. No. He would have simply said that the statements "God exists" and "God does not exist" are both equally valid possibilities and both can be accepted as true descriptions about God's existence. The steadfastness of such "believers in God" in arguing and refuting the atheists is ample proof that they do consider that rationality has a prime role to play in describing and understanding God and His Attributes.
However, these same "believers in God" then explicitly state that human rationale has no role to play in understanding or describing anything about God whenever they are cornered by their own propositions which show obvious and clear conjunction of mutually contradictory attributes with respect to God.
Here is where Islam differs from all other religions, since the primary texts of Islam constantly urge humanity at large to use their intellects in arriving at the truth of Islam. For example, the Holy Qur'an says:
And what is there after truth but error? To where, then, are you being diverted (by your whims)? (Holy Quran 10:32)
The blind and the sighted are not equal, nor are darkness and light, nor shade and heat of the sun.
And the living and the dead are not alike. (Holy Quran 35:19-22)
Notice that the Qur'an categorically states that there are certain things which completely oppose one another, and that if a thing is established to have some characteristic, its opposite characteristic cannot simultaneously subsist within that thing. The Quran also states:
Do they not, then, ponder about the Qur'an? Had it been from someone other than Allah, they would have found in it a great deal of discrepancy. (Holy Quran 4:82)
Even though the above passage may seem obvious to the lay reader, in it Allah reveals that all other scriptures, and the religions and ways they represent are deficient when it comes to the issue of internal consistency of their beliefs, especially their beliefs regarding the Supreme Lord of the Universe.
Thus, in Islam the categorization of matters is done into:
1 "Absolutely Necessary"
3 "Merely Possible"
This categorization is found in the beginning of all classical Islamic belief texts, and such categorization is extremely important when it comes to describing Allah and His Essence, since without these categories then nothing at all can be said about Allah the Exalted, not about His Power, nor His Knowledge, nor His Will, not even about His Existence.
Thus, in Islam the matters of faith are never spoken off as being contrary to rationality, or of the Muslims having to believe in certain precepts even though they are contrary to the sound mind. Granted, there are matters of the religious practices that cannot be known through reason alone (such as the number of daily prayers and their times), but the core religious beliefs of the Muslims – and especially those related to Allah and His Attributes- can very well be defended on the basis of reasoning alone without any explicit reference to scripture.
If one were to peruse the various presentations of Islamic belief (such as Aqeedah at-Tahaawiyah, Aqeedah as-Sanussiyah) and their explanations by later scholars (for example, one may read "The Aqidah of Tuan Guru" for an elucidation of Aqeedah as-Sanussiyah), one would see that great pain has been taken to ensure that the explanations provided are totally in nature with sound reasoning, and that the common layman can understand what these explanations mean, since it is incumbent upon the Muslim to know which matters are "absolutely necessary" when talking about Allah and His Attributes, which ones are "impossible" to attribute to Allah, and which ones are "merely possible".
 When both of the propositions are put together they give a result of false.
 Here we are not discussing trinity or other such doctrines at all, but we mean that if someone says "there are 20 Supreme Gods" in the sense of 20 distinct and different "Supreme Gods" that have no unity amongst them whatsoever.
 That is, whenever it is shown to them that they are taking mutually contradictory statements and attributing both of them to God.
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