Paul Zahl: Justification by Works = The Opposite of Grace

"If I can do enough of the right things, I will have established my worth. Identity is the sum of my achievements. Hence, if I can satisfy the boss, meet the needs of my spouse and children, and still do justice to my inner aspirations, then I will have proven my worth. 

There are infinite ways to prove our worth along these lines. The basic equation is this: I am what I do. It is a religious position in life because it tries to answer in practical terms the question, Who am I and what is my niche in the universe? 

On this reading, my niche is in proportion to my deeds. In Christian theology, such a position is called justification by works. It assumes that my worth is measured by my performance. Conversely, it conceals, thinly, a dark and ghastly fear: If I do not perform, I will be judged unworthy. To myself I will cease to exist." 

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