Sola Something

Two quick responses to your last post.
First, if you are saying that faith is only one way to take advantage of God's gift of salvation, I think we have a strong disagreement. In Romans 4, Paul makes a very strong argument about righteousness (a word we've over-used to mean "morally right", which fact is a forensic courtroom term to pronounce one"in right standing" with the law). In the chapter he argues that Abraham was "in right standing with God" because of his faith, NOT because of anything he may have done otherwise. Dare I say (I won't go all Latin on you ) Faith only.
One might argue that although Abraham is being talked about as being "in right standing with God" because of Faith, doesn't mean that we are to use the same means. However, that is the entire point of Paulo's argument. If we (Gentiles, not law followers; or Jews, law followers) want to be in the same position with God as Abraham was, we need to take him at his word, in faith. Abraham did this concerning the promises God made to him; first about a son, and further about a new land, multitude of descendants, and a promised land. We, Paul argues, are to do this with the promise of salvation.
Second, I seem to be missing something that you will need to explain to me (this is not sarcasm). I am not sure where this list of three unattainable virtues came from but (can you tell me) it would seem to me (speaking again from a biblical standpoint, which I do not apologize for) I would have to argue that faith and hope seem to be two virtues that humans can definitely attain, and not much else(see "Hall of Faith" list in Hebrews 11); never perfectly but, I think easier than prudence, etc.
With the above in mind, I would argue for the complete inability of humanity to accomplish any virtue properly. Thus, arguing that some are attainable and others are not seems a little strange. Just because we find one easier than another does not mean it's attainable. If we break one part of the law, we are guilty of breaking the entire law.