Some of you guys are confusing "Democracy" with "
Direct Democracy". To the best of my understanding, in present time there is no country where a "direct democracy" type of
State Government exists. By Direct democracy I mean the idea that people has the power to vote and change laws directly through the choice of majority. No, you don't have the power to vote to change law directly, not in BD not in USA, not in any modern form of democracy that currently exists (at-least not in the
state level).
What you have is a power to vote representatives who can form a majority in the parliament to change or implement specific law that the majority might want to change. So lets say (hypothetically speaking) during the civil war era 90% of US population wants no rights for the African-Americans in USA, they can't do anything about it if the elected representatives says
"Hey, this is a very immoral thing to do. We can't let it happen". Or to give a more recent (hypothetical) example, if overwhelming majority of US population want to raise the tax for the super rich but the Representative of house and senate doesn't want that there is nothing the population can do about it (immediately). They can only hope to be still passionate about this issue till the next election cycle, find and elect a majority representatives who will promise to fight to change the law and hope for the best.
When you say something like,
"hey let the people decide with their vote if they want religion groups to participate in politics" you are talking out of your *ss. Because in this case the people don't have the power (under the present form of constitution and the present form of government) to directly vote for a form of religious ideological party that the constitution clearly states is an illegitimate form of political party.
The only way you can change it is that you elect majority Representative next election cycle who promises to form a super-majority to amend parts of constitution that you don't like.
There are very very good reasons to not allow religious groups which has roots in religious ideology to take part in election. Its like making a ball out of pages of constitution where it talks about not discriminating based on religious belief and throw it in the garbage. One thing you can guarantee religion based political party to do is to discriminate against people who doesn't follow their specific beliefs. (case in point: look at Israeli parliament, which is filled with political parties based on religious based ideology)