Contrary to spells, which are used to bring love, fortune, and luck, Curses are invocations that bring evil and could
even harm others.
Conditional curses are mentioned in many parts of the Bible. A conditional curse can only
be effective if it's conditions are met or broken.
(Deuteronomy 27-28).
Then
Ben-Haded sent another message to Ahab: May the gods deal with me, be it ever so severely, if enough dust remains in Samaria
to give each men a handful." (1 Kings 20:10)
This curse was used on oneself followed by an
act of destruction (breaking an item). Using a curse not only brought evil but in some cases it also attracted demons to the
person using the curse.
In Rabbinic literature the talmudic sage Rav was able to curse others
with sterility and the sage Joshua ben Levi was able to curse crops.
