This Book " Modern Cosmology and the Quran " has, among other things, three main objectives, namely; (1) To prove the existence of God, the Creator of the whole Universe, (2) To confirm the Authenticity of the Quran, and (3) the need for religious harmony between Monotheistic Religions. The Quran has mentioned many signs in Nature which point to the existence of God and His Power. God insistently appeals to people to travel in the Earth and Heavens to seek and know His creative power, and to see how He has created every thing in the physical Universe accurately and with proportion, to look into Nature and examine the life forms and their activities, to contemplate upon the celestial bodies and the system that governs .them, and to examine the scientific signs and allusions revealed in the Quran. The principal aim is to incite the human being to reflect on the works of the creation as evidence of the Great Creator of the Universe, and to ensure that the scientific phenomena revealed in the Quran fourteen centuries ago are perfectly in conformity with modern knowledge. When people perceive this, they come to know more deeply the beauty and splendour of the Creator''s system and the infinitude of His Might. Regarding this fact, God says in the Quran: " .. Travel in the land and see how God originated the creation" (Surah 29, verse 20). " Verily, in the Heavens and the Earth are signs for those who believe"(Surah 45, verse 3). " It is the work of God Who perfected all things" (Surah 3,verse 190). As we know that the Quran was revealed to Muhammad Who was an illiterate man, and who was living in an environment dominated by ignorance. If he was the author of the Quran, how could he have written facts about Cosmology in the 7th century A.D. that today are shown to be consistent with modern science. Moreover, if somebody else had written it for him, how could he then pronounce truths of a scientific nature that no other human being could possibly have developed at the time, and all this without once making the slightest error in his pronouncements on the subject. Apart from the astronomical evidences revealed in the Quran and which are proved to be scientific facts nowadays, God has challenged disbelievers to produce a single chapter like chapters of the Quran in their beauty, eloquence and wise legislation. Ever since its revelation, fourteen centuries ago, no one has been able to meet this challenge then or today though at that time of revelation, the Arabs were very eloquent people who used to compose beautiful and excellent poetry in Arabic. With respect to this, God says in the Quran: " And if you are in doubt what we have revealed to our worshiper, then produce a chapter like it, and call your witnesses besides God if you are truthful. And if you do not do it, and you can never do it, then fear the Hell.." ( Surah 21, verse 23-25 ). The third main objective of this Book is the need for religious harmony between Monotheistic Religions, namely: Judaism, Christianity and Islam since three of them have, more or less, the same basic Divine Doctrines and Guidance that lead human kind to the right path, and because their adherents believe in the same God and worship Him, each according to the ritual activities they believe in, therefore no real reason why religious harmony does not exist between these religions. Such coexistence constitutes the bedrock of Justice and World Peace nowadays. In this connection God says in the Quran: "Say: O people of the Book ( Jews and Christians ) come to a word that is just between us and you that we will worship none but God" (Surah 3, verse 64 ). It is obvious that this Quranic verse is an invitation to inter-religious dialogue in order to find a mutual basis for peaceful co-existence and harmony between religions.