'And there is always the problem of translations and corruptions for political interests of religious texts.'
The original religious texts were already written for political interests.
That goes for the bible as for the Quran.
The bible was written for a Jewish king who was at war with the Filistines and with rival Jewish kings.
The Quran was written by a warlord.
The Old Testament may have been written for a Jewish king, I don't know enough about it.
The New Testament is a collection of documents selected from a larger group by the Romans. And a large part of it, the text written by Paul, was political, as I strongly suspect he was an agent of the Romans, whose interests were in preserving the Eastern Roman Empire (predominantly Greek city states and Palestine/Israel) So there are political reasons but not all the documents, in their original form were written for political reasons. However I would say may had been altered for political reasons. For instance I don't think there are originals found for the Gospels of Mathew, Mark, Luke and John. They are all "the Gospel according to...." Who wrote them? They are no doubt altered and for political reasons but the originals were not for political reasons. There is enough evidence to see both what is theology and what is corruption.
The Quran was not written by a warlord and I assume you are referring to the Prophet Mohammet. No only because I do not believe Mohammet was a warlord, even though he was called upon to lead an army, but because the Quran is a collection of sayings of the Prophet, which were put together after his death and indeed after his successors were murdered even though they'd stepped down for the sake of peace as it seems in what I have read. There would most probably also be alterations in some of the Quran, especially where it may have conflicted with tribal laws and customs.
These are not the sum total of holy texts. There are many documents, the Buddha's saying, the Hindu texts, Chinese, Pagan European and many, many others. These may also be corrupted in one way or another for political reasons but not necessarily all at the start. There are people who are genuinely spiritual and desiring to learn from others that are more enlightened. To say it is all for political reason is to deny religion.