He grew up on a farm in which his devout parents instilled in him Christian values along with his elder brother Jakob,[2] who enrolled in a seminary to become a priest.

To that end, in an attempt to emulate the pair and to help the poor in the spirit of charity, he joined the Society of Saint Vincent de Paul at the age of 22 and became its elected president in 1937.

[3] Mayr-Nusser served as the president of the society in its Bolzano division and in that capacity constantly visited the poor, providing them both material and spiritual assistance, in the process becoming a vocal anti-poverty advocate.

[4] In 1934, he became the head of Catholic Action in the Diocese of Trent, accepting the invitation of Pope Pius XI to broaden his lay activities.

As part of Nazi conscription during World War II he was enrolled in the SS unit in 1944 which forced him to leave his wife and newborn son for training in Prussia; he was sent off on 7 September 1944.

Mayr-Nusser's friends attempted to convince him to recant or to cease from the explosive statement, but he eschewed their offers in order to stand up for his beliefs.

On 19 March 2017 on the feast of Saint Joseph, Pope Francis described Mayr-Nusser as "a model for the lay faithful, especially for fathers, who we remember with great affection today.

However, the cause did not receive the formal approval from the Congregation for the Causes of Saints until 30 September 2005 at which point he was granted the title Servant of God and the diocesan process could begin.