Here are the complete explanation why Islam is the religion being required by God:
A Straightforward Concept of God
Unique among the religions of the world, the concept of God in Islam is completely based upon Divine Revelation. Not only is the concept of God in Islam characterized by purity and clarity, but it is also not marred by myths, superstitions or man-made philosophical ideas. In the pure and straightforward teachings of Islam, Almighty God has clearly revealed His unique nature and qualities to man in the way which He wants them to be understood. While other religions have either mixed man-made doctrines with divine revelation, or ignored the divine revelation almost completely, Islam's concept of God is based totally on what God has said about Himself. Islam's concept of God can be called pure and straightforward because there is a clear distinction made between the Creator and the created. As such, there is no ambiguity in divinity -- it is made clear that there is nothing divine or worthy of being worshipped except for Almighty God. In Islam, calling someone other than Almighty God "Lord" or "Savior" is completely prohibited because such terms compromise God's uniqueness and because all of our trust should be put in Almighty God -- who is the Most Merciful and the Controller of all affairs. The only Creator -- Almighty God -- is Unique, Eternal and Transcendent above His Creation. Everything else besides Almighty God -- meaning anything that you can see or even imagine -- is part of God's creation, and thus not worthy of worship. Almighty God, as He has described Himself in the Qur'an, is Absolutely One and "the Most Merciful of those who show mercy". Even though God is transcendent above His creation, due to His infinite Mercy He is constantly involved with the affairs of His creatures. Even though God is infinite, unique and incomprehensible, in the Holy Qur'an He has revealed Himself in a way suitable to the finite and limited human mind. By reaching out to man and sending revelations through all of His prophets, God has allowed Himself to be known through His unique and most-beautiful attributes. Because the concept of God in Islam was sent by God specifically for mankind, it appeals to the innate nature of the human being. Due to this fact, Islam does not ask man to accept irrational, ludicrous or man-made doctrines about God. The Islamic concept of God strikes a unique balance between various religions an because is avoids reducing God to just being some remote and impersonal "First Cause" or "Higher Power", while on the other hand it also teaches that a direct and personal relationship with God can be maintained without believing God to be like His creation or incarnate in it.
Direct Relationship with God
In other religions, even the ones which claim belief in "One God", people often approach God through an intermediary, such as a saint, an angel, the Virgin Mary or Jesus. However, it is only in Islam that a person is required only to pray to God. Some people also nullify a truly proper and direct relationship with Almighty God by mistakenly believing that they have a special relationship with Him simply because they are members of a certain ethnic group, tribe or "chosen people". Additionally, in Islam there are no priests or clergy -- each worshipper, man or woman, has a direct relationship with their Merciful Creator -- Almighty God. Since God is the Owner and Sustainer of everything, as well as the only one who can provide true and complete forgiveness, it is completely futile to try to approach Him through anyone else. According to the teachings of Islam, praying to or worshipping anything or anyone besides Almighty God is the greatest sin a person can commit. Even though other religions believe in God, they nullify this belief by making the grave mistake of not always approaching Him directly. Some religions even go so far as to say that human beings, due to their sinfulness, cannot approach God without an intermediary -- which mistakenly implies that God is unable or unwilling to forgive human-beings directly. Islam teaches that Almighty God has the power to do all things and that no one should ever despair of His mercy. According to the teachings of Islam, God is always ready to bestow His abundant Grace and Mercy on anyone who turns to Him in repentance. Even people who used to commit the worst sin of worshipping others besides God will be forgiven if they realize what they are doing is wrong and repent. Having a direct relationship with God, and understanding that He alone deserves worship and praise, goes hand-in-hand with the Islamic concept of God. This is because once a proper concept of God is established in the heart and mind, submission to God and complete reliance on Him alone comes naturally.
Unique Concept of Worship
According to the teachings of Islam, everything that a human being does with the pure intention of pleasing God is an act of worship. Due to this, Islam has an all encompassing concept of worship unlike any other religion. Almighty God has revealed in the Holy Qur'an that His purpose for creating human beings was to worship Him and Him alone. Like other religions, Islam has required acts of worship, however worship in Islam is not limited to rituals. Since Islam is an all-encompassing religion with guidance for all aspects of life. almost every action in a Muslim's life becomes an act of worship if it is done to build a better relationship with God. Since man's purpose in life is to worship and submit to God, worship in Islam has been defined by God Himself in an all-encompassing way. This is special uniqueness can also be seen in the fact that most other religions only require formal worship once per week, while Islam requires it five times a day. Even more importantly, all rites of formal worship in Islam are based on Divine revelation, while the modes of worship in other religions are a mixture of Divine revelation, man-made traditions, opinions of clergymen and religious councils. Additionally, in Islam acts of worship such as prayer and fasting have been described by God and His Prophet in such detail that it gives human beings a feeling of assurance that the way they are worshipping God is pleasing to Him.
Based on Authentic Sources
The preservation of the scripture of Islam -- the Holy Qur'an -- is unique among world religions. No other religion has a scripture which is both as old and as well-preserved as the one possessed by Muslims today. Even scholars who are hostile to Islam admit that the Qur'an that exists today is exactly the same as the one that existed in the time of the Prophet Muhammad. Even though many people mistakenly assume that the Qu'ran (also spelled Koran) was written by Muhammad, it is actually the literal Word of God. Not only was Muhammad known by his people to be unable to read and write, but the Holy Qur'an clearly and repeatedly exclaims that it is from Almighty God - the Lord of the Universe. Unlike other religions, the followers of Islam have always considered their scripture to be the Word of God in toto. The scriptures of other religions are made up of writings that were not considered to be scripture until many years after they were written - the letters of (St.) Paul are a good example of this. Additionally, the Holy Qur'an has always been in the possession of the common believer, and as such was circulated very widely. In this way, Muslims know that their scripture is authentic, unlike other so-called "scriptures" which are still claimed to be scripture even though their authors are unknown. The Qur'an also remained pure and authentic because unlike other scriptures, it was written down and memorized in the lifetime of the prophet that it was revealed to. Also, its wide circulation prevented scholars, clergy and religious councils from deciding what should and should not be part of the scripture -- since it was already in the hands of the people in its complete form. It has always amazed people to find out that the entire Qur'an was not only memorized word-for-word by hundreds of the companions of Prophet Muhammad, but that it has been memorized verbatim by thousands upon thousands of people until this very day in its original language of Arabic. It was only natural for Almighty God to preserve the scripture revealed to Prophet Muhammad, because he was the last Prophet and Final Messenger of God. In short, the Qu'ran is a unique scripture that has come down to us in its original form and unique language. Due to its pristine teachings and unquestionable authenticity, the Qur'an removes the need for man to wonder for himself how to worship and please God, since God Himself has clearly described these things.
An Eternal Message
Islam has just as much meaning and is just as applicable to people living in today's "modern world" as it did for people living 1400 years ago. Since the message of Islam is eternally true it is also very robust, and as such still has a strong spiritual impact on millions of people living in the world today. The Pure Monotheism of Islam, as well as its universal brotherhood, strong morals and positive outlook on life, is still very relevant and meaningful to modern man. The continued relevance and applicability to both the spiritual and worldly life of human beings from all around the word is just one of the many proofs of the Divine origin of the message of Islam. Unlike the teachings of other religions, the teachings of Islam don't need to be updated or watered-down in order to appeal to a human being living in today's troubled world. Since the teachings of Islam are both spiritually true and eternally practical, they can be lived and implemented in the daily life of a person in order to make their life more fulfilling. In short, unique among world religions, Islam has not had to sacrifice its integrity in order to be both applicable to "modern life" and to have enough spiritual impact to change people's lives.
A Complete Way of Life
Islam not just a "religion" in the traditional sense, because it is not just confined to acts of worship, morality and other aspects of personal piety. The teachings of Islam, even though they do cover religious rituals and morality, also encompass all other aspects of life. The Prophet Muhammad's mission encompassed not only spiritual and religious teachings, but also included guidance for such things as social reform, economics, politics, warfare and family life. Thus due to the diversity and success of Muhammad's mission, Muslims have clear guidance from God and His Final Prophet on all aspects of life. This goes hand-in-hand with the Islamic belief that Almighty God does not leave human beings without guidance in their daily lives -- thus His guidance is all-encompassing. Due to God's wisdom, and because Islam is the final revealed religion, the guidance that God has sent is applicable for all times and for all places. This can be seen in the fact that the guidance for some aspects of life is much more broad and flexible than others. Additionally, in the Qur'an, Almighty God has revealed to mankind that the purpose of our creation is to worship and remember God in all aspects of our life, and to follow His guidance in everything that we do. Thus Islam does not accept a secular view of government and society, but only one based on the Law of God. Nor does Islam leave it to human beings to decide what is right and wrong, good and bad, moral and immoral based on their whims, desires or man-made idea. In short, Islam does not teach people to "Render unto Caesar the things which are Caesar's" because, according to Islam, everything belongs to God. Like all of its other teachings, Islam's view of other religions is balanced, realistic and moderate. Islam doesn't view other religions as being either completely true nor completely false, but believes that all true religions were at one time divinely revealed. However, over time the teachings of the various religions, due to a variety of reasons, have become distorted and mixed with made-man ideas. But nonetheless, Muslims are required to be tolerant of other revealed religions since the Qur'an clearly says: "Let there be no compulsion in religion".
Moderation
The teachings of Islam, since they are divinely revealed, are balanced in all of their aspects. Even though Islam is an all-encompassing way of life, it preaches moderation and rejects extremism. On the one hand, Islam does not preach complete rejection of all worldly pleasures in view of the life hereafter; and on the other hand it does not teach that earthly life is just for pleasure and enjoyment. In Islam, wealth and worldly pleasures can be partaken of in this life as long as they are enjoyed in a way that is in obedience to God. However, Muslims are taught to keep in mind that the life hereafter is their ultimate goal, and therefore one should be charitable and not become too attached to worldly things. By maintaining a balance between man's spiritual and physical needs, the teachings of Islam are best suited for the needs of human beings in particular and society in general. Since Islam is based on clear guidance from God, it rejects all man-made religious excesses, such as certain forms of monasticism where people try to completely "reject the world" and other forms of extreme self-denial. Islam teaches that human beings have responsibilities at all levels -- to other individuals, to their families and to society as a whole. By maintaining a unique balance between the physical and spiritual, and between the individual and society, Islam maintains a balance in all directions.
A Positive Outlook
Most people will agree that having a strong self-esteem and a positive outlook on life is conducive to achieving happiness and success. Unique among the religions of the world, Islam's view of both the nature of the human being and the purpose of life are extremely positive. Islam's view of the nature of the human being is balanced. On the one hand they are not viewed as being inherently evil, but on the other they are not considered to be perfect - nor are they expected to be so. According to the teachings of Islam, every human being, man or woman, is born with a clean slate and is equally capable of both good and evil. Since God has bestowed limited free-will on human beings, they will ultimately be held responsible for their actions. Believing that "salvation" is based on "faith alone" reduces human life to a near meaningless and fatalistic existence. The teachings of Islam make it clear that human beings, since their nature is basically good, are capable of positive action in this life, and that the best way to achieve a balanced, happy and fulfilled life is complete submission to Almighty God. Certainly, no person can completely submit to God by simply wanting to do so, but by first realizing that none has a right to be worshipped and obeyed except for Almighty God, and then making a reasonable effort to follow God's commands, all human beings can fulfill their reason for existence - which is to worship God alone. . The Holy Qur'an tells us that "man was created weak" and thus falls into sin often. On the other hand, man is not to think of himself as so evil and corrupt so as to despair of God's mercy. As a recourse to this, and since Islam condemns self-righteousness, a pious life can only be lived by trusting in God -- since there is no power or strength except through God. As such, spiritual felicity is achieved by a combination of both faith and action. As such, the most righteous person is not one who thinks that repentance is unnecessary, but the one who admits and realizes his mistakes - and then repents. According to the word of Almighty God as revealed in the Holy Qur'an, mankind is God's trustee on earth; and as such the life of this world is a test, not a punishment. Even before God created the first man, He knew that he would sin, however God created man in spite of this. According to the Qur'an, God has bestowed on human beings a great trust and given them dignity. It is only by worshipping Almighty God, directly and without intermediaries, that a human being can fulfull their true innate nature and purpose of existence. In short, Islam is realistic. It portrays human beings just as they are and the life of the world just as it is. Since the outlook of Islam is divinely revealed is not based on wishful or negative thinking, but simply on reality. Islam also has a positive view of mankind in general, since it teaches that the best person in the sight of God is the one who is most God-conscious. In this way the truth of Islam and the universality of God's message transcends all of the barriers of race, nationality, ethnic group and economic status.
