June is traditionally the month dedicated to the Sacred Heart of Jesus. This particular devotion is by far the most popular among Roman Catholics, even surpassing devotion to the Blessed Mother. Of course, Mary would approve as her message is usually about remaining close to her Son. The devotion looks upon the physical heart of Jesus as the symbol or representation of the Divine Love for all of humanity. Devotion to the Sacred Heart was popularized by St. Margaret Mary Alacoque, a nun of the Order of the Visitation of Holy Mary who claimed to have received apparitions of Jesus Christ, the first on 27 December 1673, and the final one 18 months later, revealing the form of the devotion, the chief features being reception of Holy Communion on the first Friday of each month, Eucharistic adoration during a "Holy hour" on Thursdays, and the celebration of the Feast of the Sacred Heart. She said that in her vision she was instructed to spend an hour every Thursday night to meditate on Jesus' Agony in the Garden of Gethsemane.
On December 27, 1673, the feast of Saint John the Evangelist, Margaret Mary reported that Jesus permitted her to rest her head upon his heart, and then disclosed to her the wonders of his love, telling her that he desired to make them known to all mankind and to diffuse the treasures of his goodness, and that he had chosen her for this work.
In probably June or July, 1674, Sister Margaret Mary claimed that Jesus requested to be honored under the figure of his heart, also saying that, when he appeared radiant with love, he asked for a devotion of expiatory love: frequent reception of Communion, especially on the first Friday of the month, and the observance of the Holy hour.
During the octave of Corpus Christi, 1675, probably on June 16, the vision known as the "great apparition" reportedly took place, where Jesus said, "Behold the Heart that has so loved men ... instead of gratitude I receive from the greater part (of mankind) only ingratitude ...", and asked Margaret Mary for a feast of reparation of the Friday after the octave of Corpus Christi, bidding her consult her confessor Father Claude de la Colombière, then superior of the small Jesuit house at Paray. Solemn homage was asked on the part of the king, and the mission of propagating the new devotion was especially confided to the religious of the Visitation and to the priests of the Society of Jesus.
A few days after the "great apparition", Sister Margaret Mary reported everything she saw to Father de la Colombière, and he, acknowledging the vision as an action of the Spirit of God, consecrated himself to the Sacred Heart and directed her to write an account of the apparition. He also circulated this account, discreetly, through France and England. After his death on February 15, 1682, his journal of spiritual retreats was found to contain a copy in his handwriting of the account that he had requested of Margaret Mary, together with a few reflections on the usefulness of the devotion. This journal, including the account; an "offering" to the Sacred Heart, in which the devotion was well explained, was published at Lyons in 1684. The little book was widely read, especially at Paray. Margaret Mary reported feeling "dreadful confusion" over the book's contents, but resolved to make the best of it, approving of the book for the spreading of her cherished devotion. Outside of the Visitandines, priests, religious, and laymen espoused the devotion, particularly the Capuchins, Margaret Mary's two brothers, and some Jesuits. The Jesuit Father Croiset wrote a book called The Devotion to the Sacred Heart of Jesus, a book which Jesus is said to have told Margaret to tell Fr. Croiset to write, and Fr. Joseph de Gallifet, also a Jesuit, promoted the devotion.
The Estrela Basilica or Royal Basilica and Convent of the Most Sacred Heart of Jesus, is a basilica and ancient Carmelite convent in Lisbon, Portugal, built by order of Queen Maria I of Portugal, as a fulfilled promise for giving birth to a son (José, Prince of Brazil). The official name of the church is the Basilica of the Sacred Heart of Jesus. Construction started in 1779 and the basilica was finished in 1790, after the death of José caused by smallpox in 1788. The Estrela Basilica was the first church in the world dedicated to the Sacred Heart of Jesus.