Surah Ar-Ra'd 13:1

الٓمٓر ۚ تِلْكَ ءَايَـٰتُ ٱلْكِتَـٰبِ ۗ وَٱلَّذِىٓ أُنزِلَ إِلَيْكَ مِن رَّبِّكَ ٱلْحَقُّ وَلَـٰكِنَّ أَكْثَرَ ٱلنَّاسِ لَا يُؤْمِنُونَ

Alif, Lām, Meem, Rā. These are the verses of the Book; and what has been revealed to you from your Lord is the truth, but most of the people do not believe.

Translation: Saheeh International

Tafsir

Alif lām mīm rā’ God knows best what He means by these letters. Those these verses are the verses of the Book the Qur’ān the genitive annexation carries the meaning of partitive min ‘from’ and that which has been revealed to you from your Lord namely the Qur’ān this preceding sentence constitutes the subject the …

Excerpt from Tafsir al-Jalalayn, commentary on 13:1, via Quran.com. The reader has the full commentary and 9 more tafsirs.