The dismay that many ordinary Indian citizens feel about Prime Minister Narendra Modi’s willingness to tolerate, even encourage, the Hindu hard-liners in his own party has now spread to the financial community. Last week, Moody’s Analytics, a division of the bond rating and risk management company, warned that Mr. Modi “must keep his members in check or risk losing domestic and global credibility” — meaning, in so many words, its attractiveness to international investors.

Indian business leaders are no less alarmed. Over the weekend, N.R. Narayana Murthy, a co-founder of the Indian technology giant Infosys, lamented that “the reality today is that there is considerable fear” in the minds of the minority in India, and Kiran Mazumdar-Shaw, chairwoman and managing director of Biocon, said business leaders are “concerned with what’s happening all across the country.”

Among the sparks that have set off an extraordinary outpouring of citizen reaction are the August killing of Malleshappa Madivalappa Kalburgi, a 76-year-old critic of Hindu idolatry, and Mr. Modi’s tardy condemnation of the lynching of a Muslim man in September by a Hindu mob enraged by a rumor that his family had killed a cow and eaten its meat.

By mid-October, 35 Indian authors and poets had returned their awards to India’s National Academy of Letters. Since then, Indian sociologists, scientists, filmmakers and more than 300 Indian artists have published public statements of concern and outrage. On the occasion of his 50th birthday on Monday, the film superstar Shah Rukh Khan spoke out against intolerance and warned, “We will never be a superpower if we are not going to believe that all religions are equal.”