He is known for his priestly and pastoral work in his parish in Ars, France, resulting in the radical spiritual transformation of the community and its surroundings.

Catholics note his saintly life, mortification, persevering ministry in the sacrament of confession, and ardent devotion to the Blessed Virgin Mary.

Vianney's paternal grandparents once hosted Benedict Joseph Labre, the patron saint of the homeless, who passed through Dardilly on his pilgrimage to Rome in 1770.

[4][5] By 1790, the anticlerical Terror phase of the French Revolution forced many loyal priests to hide from the regime in order to carry out the sacraments in their parish.

The Catholic Church was re-established in France in 1802 by Napoleon Bonaparte, resulting in religious peace throughout the country, culminating in a Concordat.

He was 20 when his father allowed him to leave the farm to be taught at a "presbytery school" in the neighbouring village of Écully, conducted by the Abbé Balley.

He met a young man who volunteered to guide him back to his group, but instead led him deep into the Forez mountains, to the village of Les Noes, where deserters had gathered.

[9] Vianney lived there for fourteen months,[10] hidden in the byre attached to a farmhouse, and under the care of Claudine Fayot, a widow with four children.

[11] An imperial proclamation in March 1810 granted amnesty to all deserters,[10] enabling Vianney to go back legally to Écully, where he resumed his studies.

[13] As parish priest, Vianney realized that the Revolution's aftermath had resulted in religious ignorance and indifference, due to the devastation wrought on the Catholic Church in France.

Shaun McAfee references an incident described in the book Cure of Ars: "...a woman...told....Vianney that she was devastated because her husband had committed suicide.

In 1925 John Mary Vianney was canonized by Pope Pius XI,[17] who in 1929 made him patron saint of parish priests.

Pope John XXIII's 1960 revision, in which the Vigil of Saint Lawrence had a high rank, moved the feast to 8 August.

John Paul II visited Ars in person in 1986 in connection with the bicentenary of Vianney's birth and referred to him as a "rare example of a pastor acutely aware of his responsibilities … and a sign of courage for those who today experience the grace of being called to the priesthood.

"[12] In honour of the 150th anniversary of Vianney's death, Pope Benedict XVI declared a Year for Priests, running from the Feast of the Sacred Heart 2009–2010.

[28] As Joe Bollig explained in his article detailing the relic's unexpected stop in Kansas City, "The heart receives special veneration because in Scripture it is considered to be a person’s hidden centre of emotional, intellectual and moral activity.

"[29] By the end of the tour, "the relic [had] travelled almost 36,000 miles [58,000 km] — almost one and a half times the circumference of the Earth — and was available for over 1,200 hours of public veneration.