Fired up and full of vitriol, Hindu activist Rajeshwar Singh is on a mission to end centuries of religious diversity in India, one conversion at a time.
His voice echoing off the walls of a Protestant church across a narrow street, Singh railed against foreign faiths at an event last week to convert a Christian family to Hinduism in the rural town of Hasayan, 140 kilometers (87 miles) south of Delhi.
"We will cleanse our Hindu society. We will not let the conspiracy of church or mosque succeed in Bharat (India)," he said, standing in the family's front yard by a ritual fire lit to purify the poor, lower-caste converts.
Emboldened by Prime Minister Narendra Modi's rise to power in May, leaders of his Hindu nationalist Bharatiya Janata Party (BJP) have joined right-wing activists like Singh to openly declare India a nation of Hindus, posing a challenge to its multi-faith constitutional commitment.
About a fifth of India's 1.27 billion people identify themselves as belonging to faiths other than Hinduism.
Singh is affiliated to the Rashtriya Swayamsevak Sangh (RSS), a vast nationalist volunteer organisation that aims to unify Hindus "to carry the nation to the pinnacle of glory".
The RSS brought Modi into politics as a young man and its foot soldiers helped cement his May election victory in India's heartland, most notably in the country's most populous state of Uttar Pradesh, where Hasayan is located.
The RSS has grown in prominence since the general election, with members appointed to key cabinet posts and senior leaders deputed to the party.
Increasingly hard-line statements by RSS chief Mohan Bhagwat, an old friend of Modi, have helped motivate millions of volunteers, like Singh, already excited by the prime minister's May victory.
"Just as those who stay in England are English, those who stay in Germany are German, and those in U.S. are Americans, all those who stay in Hindustan are Hindus," Bhagwat said in August, angering India's Muslim and Christian minorities.
The debate triggered by the comments revealed a deep ideological rift between those who believe the term describes a national identity as well as a religion, and liberals who think in a multi-faith nation, all cannot be called Hindus.
Adding to the controversy, RSS-linked groups have stepped up a campaign against "Love Jihad" - a term for what they consider to be an Islamist strategy to convert Hindu women through seduction, marriage and money.