"Sins" != "Guilt" of sins
An observation someone made to me yesterday which I thought was very insightful is that Protestant Christians have a tendency when reading their bible to mentally replace the word "sins" whenever they see it with the phrase "guilt of sins" with the emphasis on the guilt. To give an example then, when the bible says things like "Christ takes away our sins"... The good little conservative protestant is going to obediently add the word "guilt" into the phrase as they read and see Christ taking away the guilt of our sins, and thus mentally add "suffering the punishment we deserved, expiating that guilt and propitiating God and thus achieving forgiveness for sin." Thus the word "sins" has been mentally changed to refer primarily to guilt, which has then opened the door wide to pouring a whole truckload of ideas about guilt into the text. Even though the New Testament virtually never mentions "guilt", it gets read into it constantly, as "sins" is read as "guilt of sins"
It struck me that such a reading stands in contrast to what I think the bible is normally meaning by "sins" - which is "sinfulness". If you read "sins" as referring to sinfulness, then phrases that Christ takes away our sins read quite differently. They are then talking about Christ causing a change in how we live, so that we live righteously instead of sinfully, that our day-to-day lives are actually changed in reality so that our actions, deeds, character, and life becomes righteous and pleasing to God instead of sinful.
There's a world of difference between the ideas of (a) causing an actual change in our lives away from sin and toward righteousness so that in the future we are free from actual sinfulness, versus (b) the idea of dealing with the guilt of our past sins. The fairly vast conceptual gulf between the two means that one and the same instance of the word "sins" occuring in the bible cannot really mean both at once. Sure, the bible could potentially teach both - sometimes teaching one and sometimes the other, but it would be stretching things to think it was teaching both at the same time in the same sentence or the same word.
My concern is that very often I see Christians reading "sins" as "guilt of sins" and as a result misreading (IMO) a passage that is talking about sinfulness and changing character rather than guilt and punishment. This occurs especially in debates about the atonement where passages talking about the removal of sin are cited as "proof" that the bible teaches Penal Substitution - yet such proof-texts rely on the reader adding the word "guilt" into the passage in the first place. To tell whether it's better to read the passage as talking about the removal of the "guilt" of sins, or to read the passage as being about the removal of "sinfulness" a greater context and careful study is needed. As a result such passages in and of themselves do not provide the proof of Penal Substitution that the people referring to them seem to see them providing, becuase they are adding the concept of "guilt" into the text and then seeing it there.