I know giving bad dua to anyone is not right even to those who have harmed you and have done wrong with you. But despite knowing it I curse someone in my heart regularly and verbally when I am discussing him with someone. I know it’s not right but I have not been able to forgive this person who wished death / verbally abused my child I can forgive someone for myself but not for my child.
Since I have left this matter on Allah from day 1 I want to stop myself from cursing this person and his mother . Is there any hadith or quranic verse which forbids bad dua so that I can remind it to myself whenever a bad dua comes for them comes in my mind and heart.
Don't know about any specific hadith or quranic verse but I once asked an aalima a similar question over the internet. There was someone who verbally abused my father and wished for death multiple times and it used to hit me terribly. This was her reply.......
If Someone curses..to some one it is Shirk..In future they have to suffer who curse on others..
There is a Hadith on Curse..
A'isha reported that some Jews came to the Prophet, may Allah bless him and grant him peace, and said, "Poison ('sam' instead of 'salam') be upon you." 'A'isha said, "And upon you and may the curse of Allah and the anger of Allah be upon you!" The Prophet said, "Easy, 'A'isha, you must be gentle. Beware of harshness and coarseness." She asked, "Didn't you hear what they said?" He said, "Didn't you hear what I said? I repeated it to them and what I said about them will be accepted and what they said about me will not be accepted...
Samura reported that the Prophet, may Allah bless him and grant him peace, said, "Do not curse one another with the cure of Allah, not the anger of Allah nor with the Fire.
Hope it helps... I would love to know more on this topic myself though.....