Qur'an 6:31

قَدْ خَسِرَ ٱلَّذِينَ كَذَّبُوا۟ بِلِقَآءِ ٱللَّهِ ۖ حَتَّىٰٓ إِذَا جَآءَتْهُمُ ٱلسَّاعَةُ بَغْتَةً قَالُوا۟ يَـٰحَسْرَتَنَا عَلَىٰ مَا فَرَّطْنَا فِيهَا وَهُمْ يَحْمِلُونَ أَوْزَارَهُمْ عَلَىٰ ظُهُورِهِمْ ۚ أَلَا سَآءَ مَا يَزِرُونَ

“Those will have lost who deny the meeting with Allāh, until when the Hour [of resurrection] comes upon them unexpectedly, they will say, "Oh, [how great is] our regret over what we neglected concerning it [i.e., the Hour]," while they bear their burdens [i.e., sins] on their backs. Unquestionably, evil is that which they bear.”

Al-An'aam 6:31 · Saheeh International