Surah Al-Bayyinah 98:3

فِيهَا كُتُبٌ قَيِّمَةٌ

Within which are correct writings [i.e., rulings and laws].

Translation: Saheeh International

Tafsir

wherein are upright precepts written rulings that are upright that is to say one who recites what contains all that and that is the Qur’ān. Thus some of them believed in it while others disbelieved.

Excerpt from Tafsir al-Jalalayn, commentary on 98:3, via Quran.com. The reader has the full commentary and 9 more tafsirs.