Giaccardo was ordained and became the first priest of the Society of St Paul. At the renewal of his Religious Profession he was given a new name, "Timothy"by Fr Alberione. Fr Timothy Giaccardo was always the right-hand of Fr Alberione. He shared with the founder the joys and sorrows, hopes and anxieties that marked the birth and growth of the congregation.
As the first House of the SSP in Alba was progressing fast, the Founder was inspired to start a new House in Rome. So he sent Fr Giaccardo to Rome in 1926. By 1929 the House of Rome, not far away from the tomb of St Paul, was well established. He was then called back to Alba and back again in Rome in 1932 where he remained till 1936. From 1936 to 1946 he was the Superior of the Mother House in Alba. In 1946 he was back in Rome and was appointed to be the first Vicar General of the Society. His health started declining in 1947 and he was diagnosed as having acute leukaemia. On the 24th of January 1948 at 1.30 p.m., he was called Home to eternal bliss after receiving the general absolution from the Founder. On the 22nd of October 1989 Fr Timothy Giaccardo was proclaimed "Blessed" by Pope John Paul II.
Responding to the Lords call, he entered the Pious Society of St Paul as an aspirant to Brotherhood on July 8, 1936 at the age of twenty. With the desire to render maximum glory to God and to benefit souls, he consecrated himself totally to God with the Religious Vows. He collaborated with the Pauline Priests in the work of evangelisation through the use of the modern means of social communication.
He felt himself unworthy of such great favours from God and often requested the assistance of others through prayer saying; "Ask the Lord that I may obtain the grace of humility". The following words express the depth to which he lived in correspondence to his calling and his mandate: "how beautiful it is to be united to the priest; to feel and to provide for the needs of souls in collaboration with him. It is a life similar to that of a mother who provides for the needs of her children".
Because of his great love for his vocation and for the Congregation, in March 1948, with the consent of his spiritual director, he made a special offering of his life to God requesting the grace of fidelity for all those who are called by God. This intention accompanied him in his total oblation and suffering until death. These are his words: "There is one thing which causes me great sorrow: the fact that some are unfaithful to their vocation".
On Saturday morning, September 4, 1948, the saintly Brother Borello died of consumption at the age of thirty two. Just before his entry in to the eternal Home, he exhorted his brothers saying: "Let us love each other always. We will see each other again in Paradise".