Surah Az-Zumar (39:56)

أَن تَقُولَ نَفْسٌ يَٰحَسْرَتَىٰ عَلَىٰ مَا فَرَّطتُ فِى جَنۢبِ ٱللَّهِ وَإِن كُنتُ لَمِنَ ٱلسَّٰخِرِينَ

lest a soul should say, “Alas for my regret over what I fell short in, regarding the side of Allah, and that I was indeed among those who scoffed.”