Muslims have been targeted by Hindu zealots.
There have been protests by prominent intellectuals at what they call a climate of rising intolerance.
Some BJP lawmakers called for the party to promote a more unifying agenda focusing on economic development, after a campaign in Bihar that sought to polarise voters along caste and religious lines.
"We have to be single mindedly focused on development, development, development," said Chandan Mitra, a BJP member of parliament.
"We can’t afford to be distracted by anything else.
"A senior BJP leader, who asked not to be named, said the problem was that Modi sidelined too many people.
"Modi thinks he can do it all at once. He wants economic growth, social and cultural revolution, to win political battles and project himself as a statesman," he said.
"If he wins then every voice of dissent can be silenced, but if he fails then every voice of dissent is going to build.
The election was one of the most vicious in recent years.
At one of dozens of election rallies addressed by Modi, he accused rival parties of snatching economic benefits from lower-caste Hindus and handing them over to a religious minority, a comment interpreted as a veiled reference to Muslims.
The election commission banned several party posters they said could incite hatred.
One banned poster showed a young Hindu woman embracing a garlanded cow, an animal sacred to Hindus.
The BJP president was also criticised for comments suggesting that if his party lost, the result would be celebrated in arch-rival Pakistan.
In contrast, Chief Minister Nitish Kumar, who led the anti-Modi alliance in Bihar, was able to trade on his record of turning around a state that was once widely considered to be among India’s most corrupt and lawless.
Arun Shourie, a minister in the last BJP government, called for a change in course. "We should be grateful to the people of Bihar because the direction has been halted," he told NDTV. Asked what went wrong with the party’s Bihar campaign, he said "everything".