SHAFAQNA – It is narrated from Imam Sajjad (AS) who said: The sins which inflict intense regret are:
Unjust murder; where God has declared it as Haram.
Cutting connection with family and close relatives and friends.
Abandoning Salaat in its allocated time; not performing Salaat in its allocated time until it is too late, will cause prolonged regret in the hereafter.
Avoiding to write a will and not repaying for the injustices.
Avoiding Zakat payment; not paying Zakat until death, and then the possessions are transferred to inheritors, and they use all they get, but punishment is for the main owner of the wealth who has not paid Zakat .