During her apparition at Valinhos on August 19, Our Lady said these remarkable words: “Pray, pray very much, and make sacrifices for sinners, for many souls go to hell because there are none to sacrifice themselves and pray for them”.
God’s grace alone can convert sinners and free them from eternal damnation. Therefore, it was necessary – not of absolute necessity, because God could have saved us differently, but in relation to the way He wanted to save us – that God became Man and offered Himself on the Cross to obtain pardon for sinners, to pay their debts, to cleanse them from their spiritual leprosy, and to restore the beautiful palace of their soul which they ruined by their sins. Therefore, all graces come from the Sacred Heart of Jesus offered on the Cross.
However, in this sentence, Our Lady attributes to our prayers and sacrifices the salvation of souls from eternal damnation, and if we do not pray, so many souls go to hell.
This means that Our Lord wants to use us as instruments to help Him to save souls. Certainly it is true that He does not need anybody to accomplish His work of salvation, but He wanted us to be partakers of this most noble work of love and mercy done on earth. He wanted it so much, that He decided to make dependent on our generosity the salvation of many. Pope Pius XII in his encyclical “Mystici Corporis” teaches: “This is a deep mystery, and an inexhaustible subject of meditation, that the salvation of many depends on the prayers and voluntary penances which the members of the Mystical Body of Jesus Christ offer for this intention.” The Sacred Heart of Jesus said to St. Margaret Mary that, “one just soul can obtain pardon for a thousand criminals”.
Our Lady repeats that “so many souls go to hell”: this is the grief of Her Immaculate Heart and the reason for Her sadness. But what is astonishing: Why do so many go to hell? Because they are wicked? Because they refuse the graces of God? Because they prefer the pleasures of the world to the will of God? Because they follow the maxims of the devil? All this is certainly right, but it is not the reason given by Our Lady here. The reason is that they have nobody to pray and offer sacrifices for them!
Behind this complaint we must discern a most solemn request: “Because nobody prays, at least you, my beloved soul visiting me here in Fatima, you please pray and do sacrifices!”
To understand this urgent request of Our Lady, we must know that God established a law, that ordinarily, He will give His graces only by human instruments. Our Lord gives His graces not by Himself, but through His instruments, the priests. Similarly, Our Lady, who is the Mediatrix of all graces, can give these graces generally only with the help of such instruments. See a famous artist, a genius: he will not paint anything if he has no instruments with which to paint. In themselves the instruments are nothing, but however, only through them the picture will be painted. Therefore, Our Lady, who wants so much the conversion and sanctification of Her children, with tears in Her eyes comes to us and begs: Would you please be so kind with me, your Mother, and help me to save souls? “Pray and do sacrifices, because so many people go to hell, for they have nobody who prays and makes sacrifices for them!”
So She, to whom I belong entirely, before whom I am only an unworthy wretch, approaches me in Valinhos like a beggar: “Help me to save souls! Be an instrument in my immaculate hands. Be not only my child and slave, be now my soldier and knight!” If I object that I am only an unworthy sinner, She will answer that She can paint beautiful pictures even with ordinary brooms!
http://fsspx.news/en/news-events/news/fatima-19-august-1917-49967