The same year he married Ms. de Oliveira, he started studies at the Theological Methodist Seminary in Porto Alegre, Brazil.
In 1939 he was transferred to the River Plate region (Argentina and Uruguay) to teach at the Theological Seminary in the city of Buenos Aires.
He was elected Bishop of the Methodist Church by the Latin American Central Conference, celebrated in Buenos Aires, in 1949.
He was invited by the Council of Bishops of the United Methodist Church to continue to exercising the Episcopal activity for another year.
Due to his Episcopal work in Bolivia for so many years, the Bolivian Government awarded him with "The Order of the Condor of Los Andes" in Cochabamba in 1969.
He also attended many ecumenical and missionary Assemblies as Delegate as well as delivering lectures at Colleges and Universities, mainly in the United States.
In 1950 he delivered lectures at the Southern Methodist University, Dallas, TX at Randolph Macon College, Ashland, VA and at the Union Theological Seminary in Cuba.
Up to 1983, he wrote about 45 volumes of Christian commentaries, poetry, drama and religious stories in Portuguese, Spanish, Italian and English.
Among his literary works in English, it is worth mentioning: "Spiritual currents in Latin America" and "Land of El Dorado".
In April 1982 he was awarded "The 1982 Upper Room Citation" at a ceremony which took place at the Central Methodist Church of Porto Alegre, Brazil.
On August 3, 1984, Bishop Barbieri married Delina Diaz, former Deaconess of the Methodist Church in Argentina and his devoted secretary for more than 50 years, who accompanied him till February 13, 1991, when he was called to the Eternal Life by God, his Master and Savior.
Bishop Barbieri fixed his residence at Ciudad Jardín Lomas del Palomar in the province of Buenos Aires, Argentina, since 1953.
His three sons are: Stelvio (Buenos Aires), Livio (Los Angeles, CA) and Flavio (Porto Alegre, Brasil).