Born in Gagos de Jarmelo in Guarda, Portugal, to Antonio and Maria (née da Natividade Martins) Saraiva, he joined the Congregation of the Missionary Sons of the Immaculate Heart of Mary, commonly known as the Claretians, and professed his vows on 22 August 1950.

He received his episcopal consecration from Cardinal Agostino Casaroli, with Archbishops Jan Pieter Schotte and Giovanni Battista Re serving as co-consecrators, on the following 2 July in the Basilica of Ss.

Pope John Paul made him Cardinal Deacon of Nostra Signora del Sacro Cuore in the consistory of 21 February 2001.

[2] Pope Benedict XVI allowed Martins to remain as Roman Postulator for the Cause for José Sánchez del Río, a 14-year-old Mexican youth and Cristeros who died a martyr.

Martins had conducted the beatification ceremony in Mexico City for the young boy as a stand-in for Pope Benedict XVI.