1) What is the Qur'an? In the Islamic faith, why is the Qur'an necessary?
2) What are the assumptions about the Qur'an? What makes the book different from all other books, or what makes it scripture? Let me say here, do not get caught up in the teachings of the Qur'an. I am discussing the book itself alone.
Sharia practice is broken down into five categories: Shahadda, Salat, Zakat, Sawm, and Hajj. I want you look at one of these practices rather objectively - what are the requirements, how do they contribute to the religious experience of the Muslim?
Remember - we cannot really answer your questions directly. We can; however, lay out some ideas and sources that can help you put together a good response.
Here is a great source:
One approach is to stress the simplicity of the Qur'an - the source above says:
"Unlike such books [other scriptures] the Qur'an formulates the tenets of faith besides communicating the ideas and views that are essential for a man of faith and belief. Similarly, it also lays down the principles of moral and ethical values for the purpose of social and familial existence."
The claim is that the Qur'an is unique and, allegedly, there has only been one single copy-type laid out through the centuries. It must be in Arabic, to minimize problems in copy and translation.
Again, from the source above:
"Those were the days when the Muslim society was quite a simple society. No other book existed besides the Qur'an, ...
The solution discusses the role of the Qur'an as scripture.