Fuṣṣilat

فَإِنْ يَصْبِرُوا فَالنَّارُ مَثْویً لَهُمْ وَإِنْ يَسْتَعْتِبُوا فَمَا هُمْ مِنَ الْمُعْتَبِينَ

24. Then if they bear the torment patiently, [it will be of no avail, since] the Fire is the home for them, and if they seek Divine Forgiveness, yet they are not of those who will ever be forgiven by Allah.

Neither patience nor crying shall be of no avail to disbelievers in Hell, since repentance and asking for Divine Forgiveness may solely help man in this world. The Arabic word mathwan indicates permanent residence and the verbal form yasta’tibu deriving from isti’ab designates request forgiveness. The blessed Verse in question is saying that Hellfire shall be disbelievers’ home whether they endure the pain or no and it shall be of no point to ask for Divine Forgiveness then since it shall be of no avail.