﴿ قَيِّمًۭا لِّيُنذِرَ بَأْسًۭا شَدِيدًۭا مِّن لَّدُنْهُ وَيُبَشِّرَ ٱلْمُؤْمِنِينَ ٱلَّذِينَ يَعْمَلُونَ ٱلصَّٰلِحَٰتِ أَنَّ لَهُمْ أَجْرًا حَسَنًۭا ﴾

“[a divine writ] unerringly straight, meant to warn [the godless] of a severe punishment from Him, and to give unto the believers who do good works the glad tiding that theirs shall be a goodly reward-”

Please check ayah 18:5 for complete tafsir.