On 10 December 1925, the Blessed Virgin, with the Child Jesus at her side above a luminous cloud, appeared to Lucia in her cell at the Dorothean house of Pontevedra. Placing one of her hands on Lucia's shoulder, she showed her a heart surrounded by thorns that she had in her other hand. The Child Jesus, pointing to it, entreated the seer with the following words: "Have pity on the Heart of your Blessed Mother, which is pierced and covered with thorns by ungrateful men at every moment with no one to make an act of reparation to remove them".
The Blessed Virgin added: "My daughter, look at my Heart surrounded with the thorns with which ungrateful men pierce me constantly through blasphemies and ingratitude. You, at least, try to console me, and tell men that I promise to assist at the hour of death with the graces necessary for salvation all those who, on the first Saturdays of five consecutive months, confess, receive Holy Communion, pray a Rosary, and keep me company for a quarter of an hour meditating on the fifteen mysteries with the intention of offering me reparation."
On 15 February 1926, the Child Jesus again appeared to Lucia in Pontevedra, asking her if she had yet divulged this devotion to His Blessed Mother. The seer explained the difficulties presented by her confessor, adding that the mother superior was ready to divulge it, but that the confessor had said that the mother superior alone could not succeed. Jesus answered, "It is true that your superior alone can do nothing, but with My grace she can do everything".
Lucia presented the problem that going to confession on Saturdays posed for some people and requested that a confession within a period of eight days before and eight days after the first Saturday be valid. Jesus answered, "Yes, it can even be within many more days, provided they are in the state of grace when they receive Me and have the intention of offering reparation to the Immaculate Heart of Mary".
Sister Lucia further raised the possibility that some people might forget to make that intention when they confessed. Our Lord answered, "They can make it in the following confession, using the first opportunity they have to confess".
During the vigil that Sister Lucia kept on the eve of 30 May 1930, Our Lord spoke in her interior and solved yet another difficulty. "The practice of this devotion will be equally acceptable on the Sunday following the First Saturday, whenever My priests, for just reasons, so grant it to souls."