Arabic is the language of God, according to Muslims. Example: the daily prayers are entirely in Arabic. I remember being taught that although God understands all languages, He has a preference for Arabic, and that in Heaven its inhabitants will speak Arabic.
For the record, Muslims believe the Qur’an is the word of God literally. Every letter, every vowel is sacred and divinely revealed. This creates interesting traditions. I remember reading about one rural restaurant that had a small swing with a Qur’an on it, decorated with cloths and flowers, and held in great honor. One would gently push the swing to reverence the Qur’an. Of course, this would be considered heretical and idolatrous by many jurists, but shows to what degree people regard the book.
Also, another thing about the sacredness of the Qur’an - one must treat and approach the Qur’an with reverence. One must be ritually pure before even touching the book, let alone reading it. One may not bring a Qur’an or recite any part of the Qur’an in dirty areas (like bathrooms). One’s feet should never point in the direction of the Qur’an. Of a pile of books, the Qur’an must be on the top. Also, there is a widespread custom/belief that reciting certain verses (or any verses, for that matter) can cure illnesses/diseases, protect from harm, bring to pass one’s wishes, ease one’s burdens, bring love, influence events and people around oneself, gain entry into Heaven, win control over spirits, avert the evil eye…and so on and so forth.
I think the argument that one cannot translate the Qur’an has more to do with the issue of translation than the Qur’an itself. It’s simply not possible to translate something from one language to another - there are nuances in words of one language that have no correspondence in other languages. All translations do are attempts to relay what another language is saying.
Now, if anyone’s read the Hebrew Bible in Hebrew and English, s/he would sense instantly that there’s a major difference between the text in the original language (including mistakes) and a translation thereof. I’ve had about 30 translations of the Hebrew Bible - none of them say the some thing. And I must say, reading the original Hebrew makes my soul soar with ecstasy - it’s soooooo powerful if one has even a slight understanding of Hebrew and Hebrew literature. (Of course, I am biased in this regard.)
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