Pain itself can be pleasurable accidentally in so far as it is accompanied by wonder, as in stage-plays; or in so far as it recalls a beloved object to one's memory, and makes one feel one's love for the thing, whose absence gives us pain. Consequently, since love is pleasant, both pain and whatever else results from love, in so far as they remind us of our love, are pleasant.
Thomas AquinasThe same fire" (which he decides to be material) " torments the damned in hell and the just in purgatory...The least pain in purgatory exceeds the greatest in this life.
Thomas AquinasDo not wish to jump immediately from the streams to the sea, because one has to go through easier things to the more difficult.
Thomas Aquinas