The earliest element of the Devotion to the Divine Mercy revealed to St. Faustina was the Image.
On February 22nd, 1931 Jesus appeared to her with rays radiating from His heart and said:
I promise that the soul that will venerate this image will not perish. I also promise victory over its enemies already here on earth, especially at the hour of death. I myself will defend it as My own glory. (Diary48)
I am offering people a vessel with which they are to keep coming for graces to the fountain of mercy. That vessel is this image with the signature” :Jesus, I trust in You.” (Diary327)
The two rays denote Blood and Water, the pale ray stands for the Water which makes souls righteous. The red ray stands for the Blood which is the life of souls. These two rays issued forth from the very depths of My tender mercy when My agonized heart was opened by a lance on the Cross. These rays shield souls from the wrath of My Father. Happy is the one who dwell in their shelter, for the just hand of God shall not lay hold of him. (Diary299)
Not in the beauty of the color, nor of the brush, lies the greatness of this image, but in My grace. (Diary313)
By means of this image I shall grant many graces to souls. It is to be a reminder of the demands of My mercy, because even the strongest faith is of no avail without works. (Diary742)
In these texts the Church’s doctrine on images, justification and grace are explained. First, by itself an image is merely a painting, no matter how beautiful and expressive. Yet, it can point us the mysteries of the faith and dispose us to grasp and receive what it represents, in this case the Divine Mercy. It is thus avessel, not the source, a reminder, not the reality. The reality is the merciful fountain of grace flowing from the pierced Heart of Christ on the Cross, and flowing out visibly to represent the visible, that is the sacramental, signs of grace, Baptism and Eucharist, standing for all the sacraments of the Church. Thus, St. John in his first letter insists on the presence of the invisible with the visible, the Spirit with the water and the Blood.
The image also reminds us that salvation is not just by faith, but by works of charity also. It takes faith to see and believe in what the Image signifies, Divine Mercy poured out from Christ upon the Cross, but it takes mercy, love going beyond the strict requirements of justice, in order to draw down mercy on oneself. “Forgive us our sins as we forgive those who sin against us” (Mt 6:12) and “the measure with which you measure will be measured out to you” (Mt 7:2) The Image of the pierced side of Christ pouring out blood and water reminds us that the Cross, love in action, is the price of mercy. “As I have loved you so also should you love one another.” (Jn 13:34)
Diary, Saint Maria Faustina Kowalska, Divine Mercy in My Soul (c) 1987 Congregation of Marians of the Immaculate Conception, Stockbridge, MA 01263. All rights reserved. Used with permission.