in 1973 costa became rector of the cathedral of maringá and later was transferred to são jorge do ivaí as parish priest. he also served in other parishes throughout the country. in 1994 he resumed his post as parochial vicar of the cathedral of maringáuntil 1997. in 1998 pope john paul ii appointed him auxiliary bishop of londrina. he was consecrated in september 1998 by the archbishop of maringá murilo ramos krieger. he was given the titular see of aquae flaviae.