He visited the cities of Rio de Janeiro, São Paulo, Curitiba, Florianópolis (then called Desterro) and Porto Alegre.

In each place he obtained authorization from the bishop and president of the province to preach the gospel, before leaving for the interior to conduct his missionary work.

[1] Dressed in the habit of a Capuchin friar, he wore sandals and carried religious objects such as a Bible, medals of Our Lady and a staff.

He gave apocalyptic sermons in which he condemned luxury and avarice, warned of the day of judgement and the torments of hell, and spoke of the possibilities of salvation.

[2] Thousands of people came to him at Cerro Campestre, in Santa Maria, Rio Grande do Sul, drawn by word of the miraculous power of his waters.

[5] He met Father Joaquim Gomes de Oliveira e Paiva, deputy provincial of Santa Catarina, in February 1849 on Arvoredo Island.

The father spoke highly of him, and perhaps as a result the Emperor Pedro II of Brazil gave him an audience and offered him gifts and favors which, as a mendicant, he could not use.

The emperor's favor may have offered him protection, when charges were later laid against him of charlatanism, illegal medicine, false promises of cure and religious imposture.

[1] In 1852 Agostini moved to Monte Palma in Paraguay, now called El Cerro del Monje and now in the Misiones Province of Argentina.

According to a plaque in the cave east of Las Cruces, New Mexico, where he spent his final two years, he told the people nearby that he'd light a fire every Friday night to let them know he was still alive.

There are many sites in the center and east of Paraná and Santa Catarina, the south of São Paulo and the north of Rio Grande do Sul, where a small altar or cross marks a place where one of the "João Marias" would have passed.