naomi24
Generally it is believed by many, if not all Muslims (and in particular by non-Muslims) that there is one authentic interpretation of the Koran.
That is simply untrue.
Even the closest companions of the Prophet (PBUH) differed from each other in understanding various verses.
Also, since there is no concept of official church in Islam no one interpretation can command following of a majority of Muslims, let alone all Muslims.
There is hardly any major issue on which Muslim 'ulama do not differ.
These differences, more often than not are due to different interpretations of the Qur'anic text.
I know you have been accused before off being an expert on all things Islamic, and you have denied that you have ever stated that.
I believe you completely.
This website explains why the Koran is open to interpretation. Basically, it's written in Arabic, and cannot be translated into other languages because if it is, it's not the Koran any more.
That means that 90% of the world's Muslims (who do not speak Arabic) have to rely on local spoken translations and interpretation.
It's totally, totally, totally up for interpretation.
http://www.islamicity.org/3407/interpreting-the-quran/