The role of religion is to make us righteous and loving, and the purpose of politics is to care for people and their welfare.
When religion and politics do not coexist, then you have corrupt politicians and pseudo-religious leaders. A religious man who is righteous and loving will definitely care for the welfare of the whole population and hence becomes a true politician. All the avatars and prophets cared for people and so were political. And a true politician can only be righteous and loving so he cannot be anything but religious.
When religions restrict freedom to worship and restrict modes of worship, they become unsuitable for creating a harmonious society. When religion becomes all encompassing and gives full freedom to pray and worship in any manner – that religion will bring righteousness and peace in people and will be suitable for any society. People think that politics and religion have to be kept separate because many religions did not allow freedom of worship and did not care equally for all people. History has shown that religion has created conflict. But irreligious societies, such as communism, have created chaos and corruption.
Today both politics and religion need reform. Politicians must become more righteous and spiritual. Religion must become broader and more spiritual to allow freedom of worship and to encompass all the wisdom in the world.