Someone who has beliefs that are against the principles of a particular religion -

Heretic (noun):
English Meaning - Someone who has beliefs that are against the principles of a particular religion. 
Bangla Meaning - উৎপথগামী, নব্যতান্ত্রিক; রাফেজি; খারেজি।
Example - Akhenaten was declared a heretic for challenging established religion by worshipping one god.

Other options, 
Iconoclast - A person who strongly opposes generally accepted beliefs and traditions. 
Disciple - A person who believes in the ideas and principles of someone famous and tries to live the way that person does or did. 
Fatalist - Someone who believes that people cannot change the way events will happen and that events, especially bad ones, cannot be avoided. 

Source: Cambridge Dictionary.