There are two types of revelation: general and private. General revelations are the teachings handed down to us from Jesus and the Apostles. These revelations ended with the Apostles and they must be believed by all Christians. Private revelations, on the other hand, have been occurring since the time of the Apostles. These are not new teachings to add to the Gospel. They are messages from God to help us in our lives, or to help others. They can also be warnings to problems which can be averted if we heed them.
Indulgences are just as misunderstood as the doctrine of Purgatory. This is a closely related doctrine and, like Purgatory, rejected by most of our Protestant brethren. Even Catholics today don’t believe in indulgences mainly due to ignorance in what it is and prefer to believe that it’s a relic of the past that was abolished by the modern Church. Of course, indulgences are still valid today and can be used to reduce your time in Purgatory.
Purgatory is a much misunderstood doctrine among Catholics. It is commonly believed that this place is a second chance to be saved, or that one can sin all they want and still be saved through its expiatory fires. Purgatory exists as a result of God’s mercy. The requirements for entering Heaven are very high because “nothing unclean will enter it” (Revelation 21:27). To go directly to Heaven you must be completely free from the stain of sin. What this means is that you cannot have any unrepented venial sin in your life, you must have fully paid the penalty for all of your sins, and you cannot have attachments to the world that takes you away from God such as materialism, jealousy, and hatred. With this in mind you can see how difficult it is to avoid Purgatory, but with the grace of God it can be done.