
The significance of the flame can already be seen since the Old Testament. First, the flames that devour the sacrifices of burnt offerings that the ancient people offered in order to purify themselves. Second, the flames on the bush that appeared and communicated with Moses.
In the Sacred Heart of Jesus, the flame represents the passionate love of Christ for humanity. In this way, we can also say that this love of Christ is the reason He revealed Himself and came down to be one with humanity. This love of Christ is what consumes Him eternally as the ultimate sacrifice to the Father and a ransom for captive and fallen humanity.
Rays
As the Heart of Christ burns with the flame of His passionate love for humanity, it radiates light. The Book of Revelation (21:23-25) reveals to us that Christ is the Light that illumines the entire heaven, as it says, “The city had no need of sun or moon to shine on it, for the glory of God gave it light, and its lamp was the Lamb. The nations will walk by its light, and to it the kings of the earth will bring their treasure. During the day its gates will never be shut, and there will be no night there.” The Light of Truth, Way, and Life shines upon us, humanity. This is the same Light that blinded the incapable eye of St. Paul and the Light that overcomes darkness.

Crown of Thorns
The crown of thorns was used by His persecutors to mock His Kingship. Christ endured all these mockeries, sufferings, and pains in every aspect of His being — physically, emotionally, psychologically, and even spiritually — without any complaint, hatred, regret, or remorse, but because of love. This crown of thorns encircles and pricks the tender Sacred Heart of Jesus. According to St. Margaret Mary, it signifies the sins of each individual. Our sins wound the Sacred Heart of Christ, who loves us most.

Cross
The cross, the primary symbol of the Christian faith, signifies the sacrificial love of God, as Christ suffered and died on the cross. Even in His last moments, He expressed no remorse but showed love for humanity and obedience to the Heavenly Father. As Christ says, “Father, forgive them, for they do not know what they do” (Luke 23:34). Death on the cross was a sentence given to criminals, considered unclean, as they were crucified outside the city of Jerusalem. Even so, Christ, being perfect Divine and perfect Human, carried the cross of the sins of the entire humanity throughout all times and places. The cross on which He was crucified and died was cleansed by His Precious Blood, conquering death and opening the gate of eternal life for humanity to be with God.
In the Sacred Heart, the cross is planted in the flaming Heart of Christ. This signifies that the cross was already in His heart since the Incarnation. This cross remained with Him throughout His entire human lifetime, His Passion, and into eternity. This cross “was filled with all the bitterness caused by the humiliations, poverty, sorrows, and contempt which His Sacred Humanity had to suffer during the course of His life and in His Passion.” The meaning of the cross comes from Christ’s love for humanity despite all the bitterness and pain. What was once a symbol of shameful and humiliating death became the symbol of faith, hope, love, and life because of the love of Christ Jesus.

Pierced Heart
The Gospel according to St. John says, “But when they came to Jesus and saw that He was already dead, they did not break his legs, but one soldier thrust his lance into His side, and immediately blood and water flowed out” (John 19:33-34). When the soldier Longinus pierced the side of Christ, it reached His Heart. From this wound, water and blood gushed forth and healed his blindness. This piercing, as the Gospel continues, “For 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 19:36-37).
In ancient times, God instructed His people during the first Passover in the Book of Exodus (12:7-13) to shed the blood of the lamb on the doorposts and lintel of their houses so they might be saved from the wrath and strike on Egypt. Meanwhile, the Gospel according to St. Matthew records the people shouting, "His blood be upon us and upon our children" (Matthew 27:25). This Precious Blood of the Lamb of God, Jesus Christ, was indeed given to humanity for their salvation. This Precious Blood continues to flow from the pierced Sacred Heart of Christ Jesus, reaching the other parts of His Body, the Church.
The heart has long symbolized love. Scientifically, the heart is the organ that pumps blood throughout the body. Psychologically, the heart is seen as the center of emotions, passion, and deepest feelings. All of these were experienced by Christ Jesus, Whose Sacred Heart is both perfect Divine and perfect Human. His Incarnation — being with us, living with us, and being one of us humans — affirms our dignity and His just and reasonable Love. It shows that we are capable of being with God again through His Love. Even though He is Omniscient (All-knowing) and already understands us, He came to us with humility and love. He showed us that He truly cares for and understands us as humans, a true love indeed. He understands our weaknesses, pains, struggles, and the bitterness of this earthly life. He carried all this bitterness of all humanity to help and save us from the eternal death that Adam and Eve brought by disobeying God and listening to the serpent, the enemy of humanity and of God, who opposed God’s good will for His creation. All of these saving and sacrificial acts of Christ are because of His love for humanity, flowing from His perfect Divinity and perfect Humanity.
Despite all this bitterness, struggle, pain, and the wounds that the soft and tender Sacred Heart of Christ Jesus received, He tells us that His Love is greater and more powerful than anything or anyone else. He is simply waiting for us to respond to the Love He has given. Moreover, He has already taught us how to respond to His love. May we come to Him and ask Him to overcome the coldness and ingratitude of our hearts toward His immense love for us.
“Sacred Heart of Jesus, I place my trust in Thee!”
“O Heart of love, I place all my trust in Thee;
for though I fear all things from my weakness,
I hope all things from Thy mercies!”
References / For Further Reading:
- Aleteia - Explaining the Strange Symbolism of the Sacred Heart
- The Catholic Leader - The Sacred Heart: A Symbol of God’s Love, a Mirror of Compassion, an Invitation to Mercy
- Welcome His Heart - The Symbols of the Sacred Heart