But in 2017, before the worst of the violence against the Rohingya, Myanmar’s state body governing Buddhism banned Ashin Wirathu from public preaching for a year, a prohibition that the monk protested by posting pictures of himself online with an “X” taped over his mouth. The same body also banned Ma Ba Tha, but the group merely changed its name and continued its activities.

Even as Ashin Wirathu was punished by the state monastic authority, he continued to roam the country to deliver his anti-Muslim sermons, including in Rakhine State, home to the Rohingya. Soon after the ethnic cleansing campaign began in 2017, he was pictured in the state news media on a tour of Northern Rakhine, the epicenter of the anti-Rohingya violence.

In his hate-filled sermons, delivered in a deceptive monotone, Ashin Wirathu has referred to Muslims as “crazy dogs” that are “breeding so fast,” “stealing our women, raping them” and “would like to occupy our country.”

He has instructed Buddhists to “make your blood boil” to ward off Muslims, whom he accuses of using hyperfertility to inundate Buddhist-majority nations.

At a rally last year in Yangon, Myanmar’s commercial capital, Ashin Wirathu said that the day Myanmar officials were brought before the International Criminal Court, which is conducting a “preliminary examination” of the Rohingya expulsion, was “the day that Wirathu holds a gun.” Such militant statements go against the peaceful tenets of Buddhism, but Ashin Wirathu has said that extreme times require extreme measures.

Although Ashin Wirathu had a poster of Ms. Aung San Suu Kyi decorating the wall of his wooden monastery in the city of Mandalay, he has accused her political party, the National League for Democracy, of secretly supporting a Muslim agenda.