Who is a believer? IS a person who grows a beard, who reads namaz 5 times, who goes to mecca in life once, who reads quran by a mere mouth and mind BUT when the time to trust ALLAH or GOD comes, he will not do so, but takes a weapon and fights instead of leaving the things to GOD or ALLAh, can be considered as a Believer?
Or a person who truly had a self experience of all pervading GOD and had established a firm relation with the omnipotent and omnipresent and all knowing GOD, and even if the person faces tough situations of facing life and death struggles, with out yielding to the anger, lust,greed but still tries to sacrifice for others, with laugh on the face, with out any fear and with out any lure for virgins or orhter material goodies can be called as a believer?
There is a difference between a believer who merely believes in something out of sensual convince and the person who believes in something out of self experiences of GOD.
For those, who donot have experience of GOD, terror will reign in this. This is the fact of all religions, not just that of Islam. The primary goal of the individual is to seek the realization of what self is,and then to realize the universalness oneness. Any one who donot go in this direction,is subjected to the ruthless treatment by the creation or mothernature,since that person is in the world of mere sensual pleasures & that person will eventually loose the valuable & precious life.