﴿ أَن تَقُولَ نَفْسٌۭ يَٰحَسْرَتَىٰ عَلَىٰ مَا فَرَّطتُ فِى جَنۢبِ ٱللَّهِ وَإِن كُنتُ لَمِنَ ٱلسَّٰخِرِينَ ﴾

“lest any human being should say [on Judgment Day], “Alas for me for having been remiss in what is due to God, and for having been indeed one of those who scoffed [at the truth]!””

Please check ayah 39:59 for complete tafsir.