Don Sergio, as his friends and supporters called him, was undoubtedly the most radical Roman Catholic Bishop of his time. Dubbed the red bishop after rightwing youth threw red paint on him after attending the 1972 Christians for Socialism Conference in Chile; Don Sergio was a leader among progressive theological thought and pastoral actions in Latin America.

Don Sergio, as his friends and supporters called him, was undoubtedly the most radical Roman Catholic Bishop of his time. Dubbed the red bishop after rightwing youth threw red paint on him after attending the 1972 Christians for Socialism Conference in Chile; Don Sergio was a leader among progressive theological thought and pastoral actions in Latin America.