P83: This is a day of fast I am offering for the souls in purgatory, especially the souls of priests. The Lord Jesus said that He could not resist the pleas of the Blessed Virgin. He flooded my mind with the following words:
Jesus: “Because you are appeasing My intense desire for souls, My little one, I will tell you about your reward. Thanks to your fast, from now on the soul of a priest will be freed from purgatory within eight days of his death. And anyone who observes this fast will obtain this grace for a suffering soul.”
(Note: If that soul died in a state of grace.)
These words were filled with such mercy and majesty that I cried because we can so effectively help the souls suffering in purgatory. My heart rejoiced when He told me of this new and great grace.
P84: The Lord Jesus asked me to write especially about how we can help souls.
Jesus: “By observing the fast I ask for, priests will be freed from purgatory on the eighth day after their death.”
p84: Mary: “My little one, Thursdays and Fridays should be considered as great days of grace. Those who offer reparation to my Divine Son on these days will receive a great grace. During the hours of reparation, the power of Satan will weaken to the degree that those making reparation pray for sinners. Nothing flashy is required, no boasting about love is necessary. It is burning in the depth of the hearts and spreads to the others.”
p98: While He was speaking to me, I got out my little lunch. On Thursday and Friday, at the Lord’s request, I eat only bread and water, and I offer it for the twelve priests and to make reparation to the Lord. Meanwhile, the Lord sat – in a spiritual way – next to me and said:
Jesus: “Oh, how this pleases Me. So few times have I enjoyed participating in such an intimate banquet. The souls that make reparation and faithfully follow My desires are so few.”
While we were eating our bread, He allowed me to feel His inner emotions and He breathed His words full of grace into my soul.
Jesus: “May our souls be in harmony. In this way, our hands will gather in unity.”
p166: Today is my fast day for the priestly souls. The Savior has asked me to fast each Monday on bread and water to free a priest soul from purgatory. Although the fast weakens me, I can do my housework and help with the children.
P214: The Reward For the Monday Fast
May 18, 1964 – Monday of Pentecost
I attended Holy Mass, and right before Communion the Lord Jesus said:
Jesus: “Since I see your firm determination to which you are faithful even on feast days, I have prepared a happy event for you. Today, from midnight on, at every hour the soul of a priest suffering in purgatory will be released.”
The Lord Jesus said this because, at His request, I fast on bread and water on Monday. I do not skip the fast even when it is a feast day. I am happy to keep the strict fast on Mondays because He promised that, by fasting on Monday, one priestly soul would come into the divine Presence. When I heard that one soul each hour would be freed, my soul was overwhelmed with the suffering that these souls still endure before coming into the divine Presence. This suffering only lasted one or two minutes, but I almost collapsed from these sorrows.
After Communion, the Lord permitted me to experience the freeing of one soul. My feelings went from one extreme to another. After experiencing the depths of suffering, I was overwhelmed with the sublime joy of that soul who arrived in the divine Presence. The state of my soul, trembling from this rapture of graces, made me feel freed for hours from the force of the earth’s gravitational pull.
P264: . . . . At breakfast and at the late afternoon snack, this [feeling dizzy when thinking about food] ceased because I took only bread and water at the request of the Lord Jesus. He had told me that only at lunch I should eat other foods, not for their taste but only to feed my body. On Monday and Thursday, I live only on bread and water. I do likewise on Friday. It is only after 6:00 p.m. that I take other nourishment.
P268: The second Friday of December 1965 was a clear day. I did the autumn work of cleaning my garden. When it became noon, I wanted to continue my work, so I put bread in my apron pocket so I could eat it while I was working.
The Lord Jesus intervened:
Jesus: “How will you say the blessing of the table? And how will you invite Me to be your guest? Tell Me, if a guest arrives, will you offer him the bread from your pocket, and will you receive him while working?”
His words dismayed me. I stopped my work, and while I washed my hands, He flooded me with His pardoning love and said:
Jesus: “Today, I want to honor you in a special way.”
Meanwhile, I covered the little table of my room with a cloth, white as the snow. On a white plate, I put slices of bread and prayed, “Come, Jesus, be our table companion…” I prayed kneeling, not standing. The presence of the Lord Jesus was so heavy upon me that I could not rise. For a time, He stood in front of me and He blessed my bread. Then He helped me to get up and said:
Jesus: “This is how you must invite Me to your table.”
p291: Both the Lord Jesus and the Blessed Virgin took turns speaking. The Blessed Virgin’s words sounded in my soul with firm, but loving power. She asked the clergy, the consecrated religious and the faithful Christians of the whole world, to fast on bread and water on Mondays when they are able to do so.
Jesus: “The Church and the whole world is in grave danger. Even with your strength, you cannot change this situation. The Most Holy Trinity alone can help you, through the concerted intercession of the Most Blessed Virgin, all the angels, all the saints, and those souls whom you have freed from purgatory.”
According to the message of the Blessed Virgin:
Mary: “When priests observe the Monday fast, in all the Holy Masses that they celebrate that week, at the moment of Consecration, they will free an innumerable number of souls from purgatory. 
When those persons consecrated to God and the faithful keep the Monday fast, they will free a multitude of souls from purgatory each time they receive Communion during that week, at the very moment they receive the Holy Body of Our Lord Jesus Christ.”
p292: While fasting, we can eat bread abundantly and drink water. We can put salt on the bread. We can take vitamins, medicines and whatever is necessary to our condition. However, we should not enjoy it. 
Mary: “Whoever usually keeps the fast, it suffices to keep it until 6:00 p.m. In this case, they should recite this very day five decades of the Rosary for the souls.”