My wife told me tonight a story that a teacher friend of hers was abused some years ago by the principal and the assistant principal. She cursed them: I mean a placed a realcurse, chicken blood and feathers and toad farts and all that. The principal died of cancer within two years and the assistant principal has had a still birth and three miscarriages.
Do curses work? I hope not.
Does prayer work?
This is a very nebulous topic that new science is working on.
The ancients have believed, no matter what your culture or tradition, that yes, strong, sustained, concentrated thought can have an affect on your environment. This is known in some traditions as prayer, meditation, or even blessings or curses. The different material or verbal elements of it only serve to re-enforce mental visualization. Ask any professional or college athlete, or sales person if mental visualization is a necessary component for success, and they will tell you yes. THOUGHTS ARE REAL PHYSICAL THINGS, that affect reality.
There is a very basic law that is recognized with this type of meddling in the universe though. What ever you send out, comes back to you. So be careful. If you pray for the forgiveness of sinners, your sins will be forgiven. However, if you work a curse on others, eventually, the cosmos will return that energy back upon you.