Oh is this so?
People always chose against who they are.
If I chose who I was, I would still be a legalistic calvanistic person who did not understand the love of God.
Saul would have remained a pharisee
Mathew would have remained a tax collector.
Peter would still be a fisherman.
I don't think you have thought this through..
Paul had to be renewed before he chose right.... as Peter etc.
I am sorry to hear that you say you where a legalistic Calvinist.. to be honest I would have to say that you may call yourself that but you obviously never knew the grace that reformed theology teaches, or if you did it did not sink into your heart.. the wonderous love of God.
Men cannot morally choose outside of their nature they 'freely' choose, but that does not make it 'free'.