"I come to tell you that they suffer in Purgatory, that they weep, and that they demand with urgent cries the help of your prayers and your good works. I seem to hear them crying from the depths of those fires which devour them: "Tell our loved ones, tell our children, tell all our relatives how great the evils are which they are making us suffer. We throw ourselves at their feet to implore the help of their prayers. Ah! Tell them that since we have been separated from them, we have been here burning in the flames!"
"Yet how quickly we could empty purgatory if we but really wished to."
"Consider then...the magnitude of these sufferings which the souls in Purgatory endure; and the means which we have of mitigating them: our prayers, our good works, and, above all, the holy sacrifice of the Mass."
"The Church, to which Jesus Christ promised the guidance of the Holy Ghost and which, consequently, can neither be mistaken herself nor mislead us, teaches us about Purgatory in a very clear and positive manner. It is certain, very certain, that there is a place where the souls of the just complete the expiation of their sins before being admitted to the glory of Paradise, which is assured them."
"The fire of Purgatory is the same as the fire of Hell; the difference between them is that the fire of Purgatory is not everlasting."
"How dearly we shall pay for all those faults that we look upon as nothing at all, like those little lies that we tell to amuse ourselves, those little scandals, the despising of the graces which God gives us at every moment, those little murmurings in the difficulties that He sends us!"
"What years of Purgatory will there be for those Christians who have no difficulty at all in deferring their prayers to another time on the excuse of having to do some pressing work! If we really desired the happiness of possessing God, we should avoid the little faults as well as the big ones, since separation from God is so frightful a torment to all these poor souls!"
"We must say many prayers for the souls of the faithful departed, for one must be so pure to enter heaven."
Source: http://www.how-to-pray-the-rosary-everyday.com/saint-john-marie-vianney-quotes.html
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