The theme of the Qur'an is the salvation of man. As the only terrestrial being capable of independent action, man is to follow certain laws for his very survival and progress. All things in the universe follow the divine laws of their own accord. Indeed, they do not possess the option of straying from this set course. In fact, the systemic functioning of the human body itself compulsorily follows the divine laws. However, man has been granted freedom of action in certain limited domains. Even in these spheres he can attain salvation if, and only if, he obeys the divine commandments.
It is to mankind that the Qur'an speaks. It is to his salvation that the Qur'an beckons. It convinces him of the existence of the Lord Creator by turning his attention to the varied and incredible phenomena of nature. It speaks to him of the brevity of life in this world and of the utter meaninglessness of wasting an entire lifetime in pursuit of the comforts herein. It makes clear to him the path which must be followed in order to be of that blessed group which becomes worthy of the entry into Paradise as of the safety from the confines of Hell.
It invites his attention to the history of those who traded the punishment of Hell in exchange for the comforts of this world. It tells him of those who were granted the entry into Paradise for having led a life of purity.
Briefly put, the Qur'an prepares man for attaining salvation both in this world and the next through obedience to the divine commandments.