613 Mitzvot
Negative Mitzvot 29
Not to fear the false prophet

Devarim (Deuteronomy) 18:22

Asher yedaber hanavi beshem YHVH velo-yiheyeh hadavar velo yavo hu hadavar asher lo-dibro YHVH bezadon dibero hanavi lo tagur mimenu.
When a prophet speaks in the name of YHVH, if the thing doesn't follow, nor happen, that is the thing which YHVH has not spoken: the prophet has spoken it presumptuously, you shall not be afraid of him.

We do not have to fear him because what he says is not from YHVH, but he has spoken presumptuously.  The false prophet says things in a certain way so that what he says is very convincing.  Just like others who lie, he is careful to say things that people want to hear, hoping they will believe that he is a true prophet and that what he says is true. Still there is no need to be afraid of his curses.

Mishle (Proverbs) 26:2  Like a fluttering sparrow, like a darting swallow, so the undeserved curse doesn't come to rest.

Bil'am is a good example of this. He was hired to curse Yisra'el, but YHVH wouldn't let him curse them.

Devarim (Deuteronomy) 23:5  Nevertheless YHVH your Elohim wouldn't listen to Bil'am; but YHVH your Elohim turned the curse into a blessing to you, because YHVH your Elohim loved you.

In cults, that the so-called prophet will make people afraid of saying his message is false by threats and curses. The Sifre also says that not only should we fear the message of the false prophet, but we should not be afraid to declare him as a false prophet.

Shalom v'brakhot
Moreh Chizkiyah Shlomo
http://www.frontiernet.com/~toddlerville/home.html

Be libi tzavanti imratecha le ma'an lo echta lach.
(Tehillim 119:11)