My observation of Christendom is that most of us tend to base our relationship with God on our performance instead of on His grace.  If we’ve performed well—whatever ‘well’ is in our opinion—then we expect God to bless us. If we haven’t done so well, our expectations are reduced accordingly.  In this sense, we live by works, rather than by grace.  We are saved by grace, but we are living by the ‘sweat’ of our own performance.  Moreover, we are always challenging ourselves and one another to ‘try harder’.  We seem to believe success in the Christian life is basically up to us; our commitment, our discipline, and our zeal, with some help from God along the way. The realization that my daily relationship with God is based on the infinite merit of Christ instead of on my own performance is very freeing and joyous experience.  But it is not meant to be a one-time experience; the truth needs to be reaffirmed daily.

Jerry Bridges, Transforming Grace