2- what is the shia belief of quran do they think it unaltered book of god?

The accepted view amongst Muslims, and especially Shiite's is that no

alteration has occurred in the holy Qoran, and that the text that is in our

hands is the whole Qoran that was revealed to the great Prophet (peace be

upon him and his progeny) without being added nor loss.

There are a lot of proofs to prove this belief; here we will summaries these

proofs in a few points.

One: Allah has said in his holy book '' verily we have sent down the

Reminder (the Qoran), and verily We (our self) unto it will certainly be the

guardian. (Al-Hijr:90)and a lot of other verses that promises its protection

and ''.Verily God fails not in(His) promise (al-ra'd:31).

Two. Since the very beginning of the revelation the holy Qoran was paid a

lot respect and attention. Not only the Muslims were attentive, the Holy

Prophet (peace be upon him and his progeny) excessively called and ordered

that the Qoran be memorized and written, and tenanted. From that time a lot

of people memorized the holy Qoran and some became'' writers of the

revelation'' protecting all the Qorans written. So with all this attention

it was close to impossible for the holy Qoran to be altered.

Three: An abundant amount of traditions from our holy infallibles mentioning

the impossibility of the Qoran being altered and denying any such accusation

shiites by following these holy sayings which are to many to be mentioned

believe that the glorious Qoran is for from being altered their scholars and

research are at the beginning of this belief.

For more historical, Qoranic, and traditional proof you may review to the

many sources written about this subject, even though unfortunately there are

not so many written or translated in the English language.

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The Qur'an orders as well as refrains, remains silent and also speaks.

It is the proof of Allah before His creasion...(sermon183-Nahjul Balagha.)