Devotion to the Sacred Heart of Jesus

31Now since it was preparation day, in order that the bodies might not remain on the cross on the sabbath, for the sabbath day of that week was a solemn one, the Jews asked Pilate that their legs be broken and they be taken down. 32So the soldiers came and broke the legs of the first and then of the other one who was crucified with Jesus. 33But when they came to Jesus and saw that he was already dead, they did not break his legs,34 but one soldier thrust his lance into his side, and immediately blood and water flowed out. 35An eyewitness has testified, and his testimony is true; he knows that he is speaking the truth, so that you also may [come to] believe. 36For this happened so that the scripture passage might be fulfilled:
“Not a bone of it will be broken.”
​And again another passage says:
“They will look upon him whom they have pierced.”
John 19:31-37
 
History
Devotion to the Sacred Heart was inspired straight from the words of Scripture. When the soldier pierced the side of Christ, his lance cut into the heart, drawing the blood out and onto the earth.   This is why more realistic depictions of the Sacred Heart show a gash in the flesh. 

Over the years, many saints have venerated the Sacred Heart of Christ. However, the most well know was St. Margaret Mary Alacoque, a French nun who lived in the 1670s.  She was called by Jesus himself "the beloved disciple of the Sacred Heart." Jesus made 12 promises to her for those who would venerate his heart. 

12 Promises of Jesus to St. Margaret Mary 
1. I will give them all the graces necessary for their state in life.
2. I will establish peace in their families.
3. I will comfort them in their trials.
4. I will be their secure refuge during life, and above all, in death.
5. I will shed abundant blessings on all their undertakings.
6. Sinners will find in my heart an infinite ocean of mercy.
7. Lukewarm souls will become fervent.
8. Fervent souls will rapidly grow in holiness and perfection.
9. I will bless everyplace where 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. The names of those who promote this devotion will be written in my Heart, never to be blotted out.
12. I promise, in the excessive mercy of my Heart, that my all-powerful love will grant to all those who receive Holy Communion on the first Friday of 9 consecutive months, the grace of final penitence; they shall not die in my disgrace nor without their sacraments.  My Divine Heart shall be their safe refuge in this last moment.

These are quite powerful and specific promises. Who wouldn't want "abundant blessings" on all our undertakings? Or peace in our families? Essentially, the devotion to the Sacred Heart is about overcoming sloth and apathy, both in this life and in matters concerning the next life.

What exactly is "sloth?" in his book The Yellow Brick Road, W.J. Bausch writes this:
                                                 "Sloth is one of the capital sins. When people think of sloth they usually think of someone who lolls around on a couch all day, popping bonbons into their mouths. But for heaven's sake, most of us run around all day like maniacs. There is never enough time: busy, busy, busy. Nobody could accuse us of sloth. We are exhausted.
                                                  But sloth is not physical laziness or indolence.  Rather, the sin of sloth has three divisions: moral sloth, spiritual sloth and intellectual sloth. Moral sloth is defined as knowing that one is set upon a damaging or deadly path but cannot muster the courage, the hope and the faith to do something different. And there is always a perfect alibi to keep from changing.  If you make suggestions for a different reaction or course of life, they come at you with anger and excuses.  All will claim they are victims and can excuse their behavior.  
                                                   The second type, spiritual sloth, is also known as "acedia," or apathy.  We might describe this as the "whatever" syndrome. We don't know, and don't care to know. We want to be uninvolved, isolated, and undisturbed. We "whatever" our  lives away. It's a type of soul-sickness that renders existence meaningless, and all choices equal and irrelevant. 
                                                   The last type of sloth is intellectual sloth - apathy towards that which makes life worth living. Intellectual laziness.  Education not for curiosity, meaning, formation and character development but for grades and achievement. If you wonder if you are intellectually lazy, look at the tv shows and magazines you typically read. Do you challenge yourself to grow and gain a gospel perspective or are you simply a consumer?
                                               Sloth, with its spin-off, apathy, is one of the deadliest sins evident in our lives today. "
      
This is the particular devotion I recommend to families who struggle with living out the gift of the Holy Spirit called Piety - the gift that helps us value spiritual matters, especially in the face of lethargy or good intentions that never materialize. Devotion to the Sacred Heart helps us to live as Christ did - being fully awake and engaged in every moment, connected to and guided by God, and really present to those around us. It helps us avoid being distracted and morose. Certainly, Jesus, as a man, must have often had thoughts like "Why am I bothering with these people?  No one is listening to me. Is it worth it? Will it make a difference?"  Also as a man, he answered all these questions positively. Yes, the people were worth it, because they were made in the image of God, who loves them. And most importantly, yes, his work, effort and sacrifice would most certainly make a difference. He did not sin = he did not allow the thoughts inspired by sloth to distract or deter him from what he needed to do, but he pushed forward in faith and hope.