Your righteousness crucifying Christ?
I don't quite follow that. Would you elaborate on that point?
And what is your definition of a work?
Do the two passages I cited constitute works? If not what you define them as?
I'd like to take a shot at this one...
If one is a churchgoer but not a believer, then one's righteousness is but that of the Pharisees...useless and barren. Upon one's conversion, one is given to understand one's utter dependance on the grace of God (and not your own works); hence a former churchgoer sees their former "righteousness" as the sin that it is. And, of course, sin is the reason for Christ's sacrifice! (How'd I do, f.C?)