An utterance of faith, as great as it is, never saved anyone. Faith is not belief in a fiction that, when uttered, suddenly turns fiction into a fact. Faith is belief in a fact. It is a God-given belief and reliance in something tangible that God has already done.
This is the major difference between true evangelism and the Christian variety: they beg you to believe in something that isn't true unless you believe it's true; they present the cross as a mere offer that is only real if you believe in it. We present the cross as a finished work. Faith cannot make it any more real than it already is.
Faith is the channel by which one understands and appreciates an ALREADY-ACCOMPLISHED REALITY.