[3][4][5] Marello's cause for sainthood resulted in his beatification on 26 September 1993 in Asti and his canonization less than a decade later on 25 November 2001 in Saint Peter's Square.

[2] Marello's mother died on 5 April 1848, and in 1852 his father decided to relocate with his children to San Martino Alfieri, where his paternal grandparents resided.

[4] Marello began his studies for the priesthood on 31 October 1856, but his father wished him to continue with his education and take up a career in business.

At one stage he considered becoming a Carthusian monk, but the new Bishop of Asti, Carlo Savio, dissuaded him, suggesting that God had other plans for him.

[3][5] Marello underwent the clerical investiture on 9 January 1864, and received both the tonsure and all minor orders from Bishop Savio on 21 December 1867.

He attended the First Vatican Council with Bishop Savio and it was there that he met Cardinal Gioacchino Pecci – the future Pope Leo XIII – who praised the priest for his virtues and talents.

[1] On 14 March 1878 he founded the Oblates of Saint Joseph which would be dedicated to caring for the poor and educating children and adolescents as well as rendering assisting bishops in whatever capacities were required.

From 5:30 to 6:15pm on 10 February he met with the pope and that evening had dinner with Cardinal Luigi Oreglia di Santo Stefano.

He received his episcopal consecration on 17 February, from Cardinal Raffaele Monaco La Valletta in the Capuchin Santa Maria della Concezione dei Cappuccini in Rome.

On 26 September 1891 he participated in a pilgrimage to Rome for the third centennial of the death of Aloysius Gonzaga and later on 4 February 1892 issued another pastoral letter on the subject of Christian education.

[4] On 28 May his two doctors thought they saw an improvement that indicated he might soon be able to leave, but the bishop's condition deteriorated on 29 May, and grew worse around 4:30pm on 30 May, when he managed with difficulty to utter a few garbled and incoherent words.

The confirmation of Marello's model life of heroic virtue allowed for Pope Paul VI to title the late bishop as Venerable on 12 May 1978.

Pope John Paul II approved the miracle on 2 April 1993 and presided over Marello's beatification in Asti on 26 September 1993.

[4] The second miracle that was investigated took place in Peru and was the simultaneous healing of the children Alfredo and Isilia Chávez León who were both cured from bronchopneumonia.

John Paul II issued his final approval to this miracle on 18 December 2000 and in a 13 March 2001 consistory scheduled the date.