Allah has sent down the best statement: a consistent Book wherein is (39:23)

﴿اللَّهُ نَزَّلَ أَحْسَنَ الْحَدِيثِ كِتَابًا مُّتَشَابِهًا مَّثَانِيَ تَقْشَعِرُّ مِنْهُ جُلُودُ الَّذِينَ يَخْشَوْنَ رَبَّهُمْ ثُمَّ تَلِينُ جُلُودُهُمْ وَقُلُوبُهُمْ إِلَىٰ ذِكْرِ اللَّهِ ۚ ذَٰلِكَ هُدَى اللَّهِ يَهْدِي بِهِ مَن يَشَاءُ ۚ وَمَن يُضْلِلِ اللَّهُ فَمَا لَهُ مِنْ هَادٍ﴾
[ الزمر: 23]

39:23 Allah has sent down the best statement: a consistent Book wherein is reiteration. The skins shiver therefrom of those who fear their Lord; then their skins and their hearts relax at the remembrance of Allah. That is the guidance of Allah by which He guides whom He wills. And one whom Allah leaves astray - for him there is no guide.

Allah sent down to His Messenger, Muhammad ( peace be upon him ), the Qur’ān which is the best speech.
He sent it down in a manner that part of it resembles other parts in their truthfulness, beauty and consistency without disagreement.
It contains numerous stories and rulings, promises and threats, attributes of the people of truth, attributes of the people of falsehood etc.
The skins of those who are in awe of their Lord tremble when they hear the threats and warnings it contains.
Then their skins and their hearts soften to Allah’s remembrance when they hear the hope and good news it contains.
What has been mentioned, about the Qur’ān and its effect, is Allah’s guidance by which He guides whoever He wills.
Those whom Allah leaves astray and does not guide, have no one to guide them.

Allah has sent down the best statement, a Book (this Quran), its parts resembling each other in goodness and truth, oft-repeated. The skins of those who fear their Lord shiver from it (when they recite it or hear it). Then their skin and their heart soften to the remembrance of Allah. That is the guidance of Allah. He Guides therewith whom He pleases and whomever Allah sends astray, for him there is no guide.

phonetic Transliteration

Allahu nazzala ahsana alhadeethi kitaban mutashabihan mathaniya taqshaAAirru minhu juloodu allatheena yakhshawna rabbahum thumma taleenu julooduhum waquloobuhum ila thikri Allahi thalika huda Allahi yahdee bihi man yashao waman yudlili Allahu fama lahu min hadin

Abdullah Yusuf Ali - Translation

Allah has revealed (from time to time) the most beautiful Message in the form of a Book, consistent with itself, (yet) repeating (its teaching in various aspects): the skins of those who fear their Lord tremble thereat; then their skins and their hearts do soften to the celebration of Allah's praises. Such is the guidance of Allah: He guides therewith whom He pleases, but such as Allah leaves to stray, can have none to guide.

Safi-ur-Rahman al-Mubarakpuri

Allah has sent down the Best Statement, a Book, its parts resembling each other, (and) oft-repeated. The skins of those who fear their Lord shiver from it. Then their skin and their heart soften to the remembrance of Allah. That is the guidance of Allah. He guides therewith whom He wills; and whomever Allah sends astray, for him there is no guide.

Page 461 English transliteration