According to the Catholic church, an indulgence is a sacrifice made to reduce the time one needs to spend in purgatory after death. There are two kinds, plenerary (all sins forgiven) and partial (some sins forgiven). In the middle ages a scandal came to light where bishops would sell "indulgences" to weathy people so that the rich could live however they wanted. This is one of the catalysts for the Protestant Reformation.
Catholic AnswerMartin Luther had a lot of problems, all of them dealing with the Church's insistence that he lead a moral life to attain salvation. He decided that he didn't need to lead a moral life because faith alone was enough to save him. To justify his position, he mutilated the Bible, he rewrote Romans, putting the word "alone" after faith, and attempted to throw out the book of James as it had the word "alone" in it already: James 2:24: "Do you see that by works a man is justified and NOT BY FAITH ALONE." Indulgences are granted from the Church's treasury to help man deal with the damage he has done to the Body of Christ by his sins. Martin Luther did not want to acknowledge the principal, thus, for example, he threw out the entire book of 2 Maccabees which speaks of us making atonement for the dead that they may be loosed from their sins. (2 Maccabees 12:43-46). For this he got to throw out prayer for the dead along with atonement for sin. Indulgences could be earned for any of the three works of penance: fasting, prayer, almsgiving. Because of Martin Luther, and his cohorts, we can no longer earn indulgences for almsgiving: .This is another, "when did you stop beating your wife?" question. You can't answer it, because the premise is a lie. The Catholic Church never sold indulgences, ever. Nor, for that matter do indulgences have anything to do with forgiving sin. You need to understand the Christian concept of the Body of Christ: we are all members of the Body of Christ by our baptism. When one of us sins, we hurt the entire Body. Our Blessed Lord died on the cross to forgive our sins. We apply that forgiveness to ourselves in various ways, the first of which is baptism which wipes out everything up to that point in our lives. After baptism, Our Blessed Lord provided another Sacrament to remove serious sin (and venial {less serious}), that is confession. When you go to confession you must have contrition for your sins, confess all of them, and resolve to never to them again. Let me see if I can explain this another way:.To understand indulgences you must first understand sin and its consequences:.When one sins, one damages the Body of Christ, as, by our Baptism, we are all members of the Body of Christ, and everything we do, for good or ill, affects everyone..Say you are in the street in your neighborhood playing softball. You hit one and it goes flying across the street and through Mrs. Neighbor's front window. You put the bat down, walk across the street, knock on the door, and apologize to Mrs. Neighbor. She forgives you, since you were nice, and owned up to your fault. Up until now we have the basic scenario of someone going into confession and confessing their sins..But wait, notice that in my example, the window is still broken. You have to go home and confess to your father and mother that you broke the window, they, in turn, take your allowance for the next several years and pay to have the window fixed. The broken window is the example of how we damage the Body of Christ. The allowance that you have to fork over for the next several years is your penance..Now, an indulgence is based on the fact that when Jesus was a man living on the earth, his mother, and the other saints down through the centuries, have done more good works than they need to do their penances (in the case of Our Blessed Lord, and His mother, they had no need of penances, so all their good works are surplus), so, the Church, through Her power of the keys, can apply the merits of those good works to your penance. So in the example above, the indulgence is your parents fixing the window for you, and you are still going to get your allowance. You might have to fork over some of it to help, but they are not going to impoverish you for the next several years..That is what an indulgence is: it is the application of the good works of the saints to make up for your penances. Please note that they are only applicable to someone in a state of grace who has already been forgiven. They have NOTHING to do with the remission of sin. Without prior remission of sin, there can be no indulgence.. Now, any good work can be used to obtain an indulgence in the Church, the classic works of penance are prayer, fasting, and almsgiving. The one that causes so much trouble back during the protestant revolt was an indulgence attached to almsgiving. For instance, you can earn a plenary indulgence now if you go to confession, go to Mass, receive Holy Communion, pray for the Holy Father, and do a good work, say a Rosary in front of the Blessed Sacrament, or in a family group. You used to be able to earn a Plenary Indulgence for all the same conditions, but instead of saying the Rosary, you could donate ANY sum of money for some good work the Church was involved with. In this particular case, it was rebuilding St. Peter's Basilica. Because of all the hysterics and false rumors, that is no longer possible. Bottom line? The Church has never sold indulgences, ever.
Roman Catholic AnswerFor the main part, conflicts between protestants and Catholics have been more conflicts between different peoples who happen to be Catholic or protestant. For instance, in Ireland, the Irish, who were fighting to save their nation, all happened to be Catholic, while the English were all protestant. Other conflicts have come about because of ignorance and/or intolerance. For the most part protestants have been brought up to believe that Catholics are not Christian and are worse than pagans. This has been very unfortunate, with disastrous results in some cases. I, myself, was brought up in a protestant household and Catholic beliefs were beyond the pale. I have heard that everbody was warned at my parents wedding to not tell my mother's grandmother that the bridegroom's mother was Catholic. All very sad.