After graduating from the Jesuit St. Stanislaus High School, he entered the seminary of the Archdiocese of Bombay and was later ordained to the priesthood by Valerian Gracias on 8 December 1958.

[4] Dias worked in the Vatican Secretariat of State preparing the 1964 visit of Pope Paul VI to India, during which he was raised to the rank of Privy Chamberlain of His Holiness on 4 December.

[4] From 1965 to 1973, he served as secretary of the nunciatures in Denmark, Sweden, Norway, Iceland, Finland, Indonesia, Madagascar, Réunion, the Comoro Islands and Mauritius.

[4] On 8 May 1981, Dias was appointed Titular Archbishop of Rusibisir and Apostolic Pro-Nuncio to Ghana, Togo and Benin by Pope John Paul II.

He received his episcopal consecration on the following 19 June from Cardinal Agostino Casaroli, with Archbishops Achille Silvestrini and Duraisamy Simon Lourdusamy serving as co-consecrators, at St. Peter's Basilica.

[7] He was an outspoken supporter of the controversial 2000 document of the Congregation for the Doctrine of the Faith Dominus Iesus, which declared that non-Catholics "are in a gravely deficient situation in comparison with those who, in the Church, have the fullness of the means of salvation.

[4] He was shortly afterwards named to the Council of Cardinals for the Study of the Organizational and Economic Problems of the Holy See on 10 March 2001, and served as one of the three presidents at the 10th Ordinary Assembly of the World Synod of Bishops from September to October 2001.

He said: "When we live myopically in the fleeting present, oblivious of our past heritage and apostolic traditions, we could well be suffering from spiritual Alzheimer's.