There is no point in blaming politicians for religious violence. Politicians are just exploiting the divide which is there already. If you have infighting in your family an outsider can act as a catalyst and aggravate your problems.
There is only one solution which is never practical. Hindus respect Muslims and Christians and admit their believes are also right along with their own believes. Similarly Christians should also respect Hindus and Muslims and admit their believes as right . Muslims also should respect Hindu and Christian religions and their believes.
If any one of these major religions in India thinks they are superior to others there won't be peace. If any one of them thinks only they are right then there is no peace. This is what exactly happening in India.
Religious Books and believes which spreads hatred against other religions should be banned.