Vicar general
After studying at the seminary in Angra, Nunes went to Macau as a missionary on 4 June 1903, and was ordained to the priesthood on the following 26 July. He then did pastoral work and taught at Macau's seminary until 1906. Nunes was named Vicar general of Macau and Timor from 1906 to 1913, when he began missionary work in Timor. He became Vicar capitular of Macau on 21 February 1917.