One of the Church’s most enduring problems has been the persistence of sin in the lives of professing Christian people. That is to say, why don’t Christians seem to be all that different from non-Christians? Different churches have dealt with this question in different ways. At the time of the Protestant Reformation, the question took on renewed urgency as new translations of the New Testament allowed theologians to rediscover the way that the Apostle Paul, in particular, spoke about the relationship between Jesus’s death and our lives and faith. At the risk of oversimplification, the ancient pre-Christian approach—developed by Aristotle and baptized by Thomas Aquinas—understood God to be an assumed “good” towards which people should strive. By greater and greater participation in this “good,” people would move upward, toward greater and greater degrees of holiness. The Reformers noticed a crucial flaw in this scheme: the “better” people got, or the closer to God they came, the less need for Christ they would have. Like the proverb “Give a man a fish and you feed him for a day; teach a man to fish and you feed him for a lifetime,” Jesus was viewed as the great fishing guide in the sky.

The Reformers believed that people who believe in Jesus live by faith in him, not by participation or growth in holiness. This does not mean that the Christian life is unconcerned with doing good, only that it is important the good that might be done not cause us to forget the fundamental neediness of the person doing it. In other words, the Christian is someone who needs to be given a fish every day. Luther described this state as being “simultaneously justified and sinful at the same time,” or simul iustus et peccator in the Latin. So Christians are two things at the same time, both enduringly sinful and completely forgiven and justified by the imputed righteousness of Christ. Their identity is dual. This is not a half-and-half relationship; it is 100% and 100%. Paradoxically, we are fully saved and made righteous in Christ, and at the same time we are still the same old sinner we used to be. A Christian is seen by God as “hidden in Christ” (Colossians 3:2). As the Apostle Paul puts it, “I have been crucified with Christ. It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me” (Galatians 2:20).


We hope the following guide will explain how certain technical terms are used on the Mockingbird site.

None of these definitions are, or could possibly be, comprehensive. Hundreds of books have been written on each. We are aiming, instead, via a few broad strokes, to give a sense of how the terms are being used. It should be noted that these terms are sometimes used as shorthand for their philosophical implications, or centrifugal outworkings.

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