Luther saw quite clearly that people for whom the gospel is theory, a ‘human figment and idea’, are bound to demand that it must now be put into practice. The pattern of theory and practice leads them astray, so that they say: ‘Faith is not enough, we must now perform works’. In other words, sanctification must be added to justification, in a second act, as the human response to God’s word. Luther saw that in the very same degree to which the word that initiates faith pales in theory and idea, the demand that idea be realized in practice is inevitable. The theorization of faith is matched by a moralization, ethicization of life… If faith is neither a theory nor the praxis of self-realization, but passive righteousness - God’s work in us, which we experience sufferingly and thus die to justifying thinking as well as to justifying action - then faith is by no means thoughtless, any more than it is inactive. On the contrary: through faith, thinking as well as action becomes new.
Oswald Bayer as quoted by Bernd Wannenwetsch in Political Worship