oppositeman, great topic.
The Holy Souls is one of my favorite meditations, thanks to Father Paul O'Sullivan's "How to Avoid Purgatory"
I'm embarrassed to say I'm not familiar with Purgatory Explained / S.J. Fr. F.X. Schouppe, but I'll get familiar with it ASAP. Thank you.
Excerpts from "from How To Avoid Purgatory" :
1. In every prayer you say, every Mass you hear, every Communion you receive, every good work you perform, have the express intention of imploring God to grant you a holy and happy death and no Purgatory. Surely God will hear a prayer said with such confidence and perseverance.
2. Always wish to do God's will. It is in every sense the best for you. When you do or seek anything that is not God's will, you are sure to suffer. Say fervently, therefore, each time you recite the Our Father: "Thy will be done"
3. Accept all the sufferings, sorrows, pains and disappointments of life, be they great or small: ill health, loss of goods, the death of your dear ones, heat or cold, rain or sunshine, as coming from God. Bear them calmly and patiently for love of Him and in penance for your sins. Of course one may use all his efforts to ward off trouble and pain, but when one cannot avoid them let him bear them manfully. Impatience and revolt make sufferings vastly greater and more difficult to bear.
4. Christ's life and actions are so many lessons for us to imitate.
The greatest act in His life was His Passion. As He had a Passion, so each one of us has a passion. Our passion consists in the sufferings and labors of every day. The penance God imposed on man for sin was to gain his bread in the sweat of his brow. Therefore, let us do our work, accept its disappointments and hardships, and bear our pains in union with the Passion of Christ. We gain more merit by a little pain than by years of pleasure.
5. Forgive all injuries and offenses, for in proportion as we forgive others, God forgives us.
6. Avoid mortal sins and deliberate venial sins and break off all bad habits. Then it will be relatively easy to satisfy God's justice for sins of frailty. Above all, avoid sins against charity and against chastity, whether in thought, word or deed, for these sins [and the expiation for them] are the reason why many souls are detained in Purgatory for long years.
7. If afraid of doing much, do many little things, acts of kindness and charity, give the alms you can, cultivate regularity of life, method in work, and punctuality in the performance of duty; don't grumble or complain when things are not as you please; don't censure and complain of others; never refuse to do a favor to others when it is possible. These and suchlike little acts are a splendid penance.
8. Do all in your power for the Holy Souls in Purgatory. Pray for them constantly, get others to do so, join the Association of the Holy Souls and ask all those you know to do likewise. The Holy Souls will repay you most generously.
9. There is no way more powerful of obtaining from God a most holy and happy death than by weekly Confession, daily Mass and daily Communion.
10. A daily visit to the Blessed Sacrament--it need only be three or four minutes--is an easy way of obtaining the same grace. Kneeling in the presence of Jesus with eyes fixed on the Tabernacle, sure that He is looking at us, let us for a few minutes repeat some little prayer like these: "My Jesus, mercy." "My Jesus, have pity on me, a sinner" "My Jesus, I love You" "My Jesus, give me a happy death"
a) Let us give all the alms we can afford;
b) Let us have said all the Masses in our power;
c) Let us hear as many more as is possible;
d) Let us offer all our pains and sufferings for the relief of the Holy Souls.
We shall thus deliver countless souls from Purgatory, who will repay us ten thousand times over.