The Sacred Heart of Jesus is a religious devotion to Jesus physical heart. A divine love for humanity.

The picture is often deplicted as a flaming heart, pierced by the sword, and surrounded by a crown of thorns, and bleeding.
The wounds and crown represent Jesus death, and the fire love.
Feast of the Sacred Heart is always celebrated 19 days after Pentecost.
BACK TO JESUS INDEX
DEVOTION TO THE SACRED HEART OF JESUS
HISTORY OF:
From the time of John the Evangelist there has always been a devotion to the love of God. However, there is nothing to indicate that during the first 10 centuries, any worship was devoted to the wounded Heart of Jesus.
During the 11th and 12th centuries the devotion was noting in the Benedictine and Cistercian monastaries.
From the 13th to the 15th centuries this devotion began to spread to Franciscans, Dominicans, Carthusians etc. The 5 wounds being a part of the Franciscan teachings.
In the 16th century, the devotion turned from laward to outward and more established as a devotion with prayers already formulated and special exercises, found in the writings of the Carthusians.
The image of the Sacred Heart was everywhere in evidence, largely due to the Franciscan devotion to the 5 wounds.The Jesuits used the image on their title-page of their books and in the walls of their churches.
HISTORY OF (CON) , VISIONS OF ST MARGARET MARY, PROMISES OF THE SACRED HEART
Visions of St Margaret Mary
St Margaret Mary claimed to have visions from Jesus that promised her to rest her head on His heart.
Then told her of His Love, telling her that He desired to make this known to all mankind. In 1674, Margaret Mary claimed that Jesus requested to be honored under the figure of the His Heart of flesh. Devotion of love, frequent receiving of Communion, especially on the 1st Friday of the month and the observance of the Holy Hour.
During the  day before Corpus Christi in 1675, the vision known as the "great apparition" took place. Jesus told her "Behold the Heart that has so loved man ..instead of gratitude I receive from the greater part ingratitude." and asked her for a feast day for reparation.
Asking her to consult Fr de la Colombiere then superior of the Jesuit house of Paray.
PROMISES OF THE SACRED HEART
1-I will give them all the graces necessary in their state of life.
2- I will establish peace in their homes.
3.- I will comfort them in all their afflictions
4- I wil be their secure refuge during life, and about all in death.
5- I will bestow abundant blessings upon all their undertakings.
6- Sinners shall find in My Heart the source and the infinite ocean of mercy.
7- Tepid souls shall become fervent.
8- Fervent souls shall quickly mount to high perfection
9.- I will bless every place in which an image of My Heart shall be exposed and honored.
10- I will give to priests the gift of  touching the most hardened hearts.
11- Those who shall promote this devotion shall have their names written.
12. I promise you in the excessive mercy of My Heart and My all-powerful love will grant to all those who communicate on the 1st Friday in nine consecutive months the grace of final penitence; they shall not die in My disgrace nor without receiving their Sacraments. My divine Heart shall be their safe refuge in their last moment.
.
History (Con)

Never the less remained private, until Jean Eudes an apostle of the Heart of Mary, his devotion to the Sacred Heart of Jesus led to public awareness and a feast day being named and celebrated.

This feast day is celebrated in June.
More information
See
Sister Faustina
Under SAINTS

DIVINE MERCY
Under JESUS
PRAYERS AND THE LITANY OF THE SACRED HEART can be found in
PRAYERS.
WORSHIP AND DEVOTION
The acts of consecration, reparation, and devotion were introduced when the feast of the Sacred Heart was declared. Pope Pius VI praised devotion to the Sacred Heart. Finally by order of Leo XIII, he consecrated every human to the Sacred Heart. He called it the "great act", and told them that it was told to him from a religious woman who had received the instruction in a vision from Jesus. Worship of the Sacred Heart consists of Hymns, and prayers. Including the Litany to the Sacred Heart.