Surah At-Talaq 65:10

أَعَدَّ ٱللَّهُ لَهُمْ عَذَابًا شَدِيدًا ۖ فَٱتَّقُوا۟ ٱللَّهَ يَـٰٓأُو۟لِى ٱلْأَلْبَـٰبِ ٱلَّذِينَ ءَامَنُوا۟ ۚ قَدْ أَنزَلَ ٱللَّهُ إِلَيْكُمْ ذِكْرًا

Allāh has prepared for them a severe punishment; so fear Allāh, O you of understanding who have believed. Allāh has sent down to you a message [i.e., the Qur’ān].

Translation: Saheeh International

Tafsir

God has prepared for them a severe chastisement the reiteration of the threat is for emphasis. So fear God O people of pith O possessors of intellect you who believe! this is a description of the vocative or an explication of it God has certainly revealed to you a source of remembrance that is the Qur’ān;

Excerpt from Tafsir al-Jalalayn, commentary on 65:10, via Quran.com. The reader has the full commentary and 9 more tafsirs.