According to Dictionary.com, purgatory is “a condition or place in which the souls of those dying...are purified...from sins.” Essentially, purgatory is part of the Catholic doctrine of faith where a “final purification” occurs in order to “achieve the holiness necessary to enter...heaven,” (Catechism of the Catholic Church, CCC 1030-31).
The famous theologian Augustine – considered a founding father of Christianity – advocated praying for the dead. He felt prayer removed the final traces of sin after a human passed away. According to Catholic Online, St. Augustine lead a life of drinking and sexual immorality. Could Augustine’s inner guilt from his personal experiences with sin lead him to embrace the idea of purgatory? Perhaps so.
In his book, Enchiridion on Faith, Hope and Love, Augustine says,
It is a matter that may be inquired into, and either ascertained or left doubtful, whether some believers shall pass through a kind of purgatorial fire, and in proportion as they have loved with more or less devotion the goods that perish, be less or more quickly delivered from it. This cannot, however, be the case of any of those of whom it is said, that they shall not inherit the kingdom of God, unless after suitable repentance their sins be forgiven them (Handbook on Faith, Hope, and Love, Chapter 69).