SHAFAQNA – A believer should know that if God forbid he /she is dominated by the party of Satan and dies,the time will come when no intercession is effective and nothing else can be done, on that day regret and remorse have no use. As Ayah 39 of Surah Al-Maryam says: “And warn them of the Day of Regret (Day of Resurrection) when matters will be decided; they are so neglectful and do not believe.”
It must be said that duration of a day in the hereafter is not the same as one day in this world, only Allah (SWT) knows the length of the Day of Regret. Of course we hear about the Day of Judgment but we do not know much about the regrets on that day. There are regrets that have no end and remorse without limits.
 Sharhe Hadith Jonood wa Jahl, Page 53.