"One great advantage arising from the thought of Purgatory is that it inspires with a spirit of penance and self-denial; for it reminds us that Divine Justice, though severe, is not blind and never punishes the same fault twice, since if expiation is made in this world, it will not be required in the next. Knowing that justice so inflexible and unrelenting in Purgatory is easily disarmed here on earth, we naturally feel an earnest desire to escape the terrible fire of Purgatory, which can only punish sins unexpiated, and consequently we take care to leave few stains to be cleansed away hereafter.
"God in His infinite goodness affords us the opportunity of paying the debt contracted by a deliberate act by means of a voluntary satisfaction, and only chastises us in the other world because we have not had the courage to punish ourselves in this. Our interest, therefore, lies in forestalling His judgments and justice by self-imposed penances, for however severe they may be, they fall far short of those of Purgatory. This thought fills the soul with a holy courage to embrace mortification and penance generously, saying: 'better settle now my accounts with God; better take advantage of His mercy to satisfy His justice; better pay my debts now while I can do so easily. This is my resolve and firm determination.' "
~ From Stories About Purgatory and What They Reveal, Tan Publishers ~