The Protestant church came into creation essentially related to the frustration and the dismay of the quite obvious corruption of the Catholic church; of which, one of the most corrupting aspects of that Catholic church, was the sale, more or less, of Catholic sanctioned indulgences to the faithful, for a monetary price, that would thereby alleviate and mitigate temporal sins from that individual soul, so that such would not suffer in purgatory or hell for the commission of those very sins, that the church as God's representative on earth, had "indulged" or, that is, forgiven.
The very thing about sinning is that most people that have done wrong actions and wrong deeds, are usually fairly cognizant about them, though, there are many that create lives of denial and justifications to placate their conscience, but basically, in truth, those that sin, know that they are sinners. The fact that people know that they have done wrong, quite obviously creates a real conundrum for those that believe that their soul survives physical death, and of further concern is that the afterlife necessitates a thorough review of the acts that a particular person has committed or omitted, in painstaking detail.
While there is many a person, that takes solace, correct or not, that Jesus has died for all our sins, and that if we accept Jesus in our heart, that our sins are truly forgiven by God, such, appears to be, one of those shortcuts to salvation, that doesn't appear to be fair or just. Whether the former is literally true or not, one can make a very strong case, that those that have sinned like the devil, and then at the 11th hour, through sincere repentance, are somehow forgiven and absolved of all guilt from that sin, are probably going to find, that an indulgence such as that, does not now, nor has it ever, existed.
Essentially, any preaching that puts together some formula, that somehow absolves the person of heinous acts of commission, without taking into the account, the other parties or principalities that have been hurt and damaged by those actions, probably doesn't have it correct. Be that as it may, true repentance, necessitates propitiation of sins through the overt acts of goodness to overcome and to offset wrong deeds so done. This should appear rather obvious, for those that have done wrong, and truly recognize it, almost always have a deep and abiding desire to make up for those wrongs by correct and right actions, and implicitly recognize, that they need to.
So too, when we look at modern day indulgences, the most obvious of them all, is the very same game plan and structure that existed when the Catholic church openly sold such indulgences; which is basically, that those that have money, and lots of it, are somehow able to pay their way into Heaven, through their generous acts of charity and foundations while here on earth. The very truth of the matter is that you cannot now nor could you ever buy your way into Heaven, or buy indulgences for the remission of sins, for God freely gives and cannot be enticed by the entreaties of mere mortal man. Rather, while money works extremely effectively here on this planet, for virtually anything of substance, it does not work outside of this material plane, and all those that trust in the almighty dollar to get them certain privileges, immunities, and favors wherever they so sojourn, are going to ultimately find to their dismay, that being frozen up to their neck in hell, leaves them no choices at all.