There was a big debate in the Lutheran community in the late 1500's over the correlation of faith and works - called the Majoristic Controversy. This is from the "Evangelical Dictionary of Theology"
"Georg Major, a pupil of Melanchthon, declared that good works are necessary to salvation. A counter attack was made by the Gnesio-Lutherans, led by Flacius and Amsdorf, but especially the latter overshot the mark by is counterassertion that "good works are harmful to salvation" (although Luther had on occasion so expressed himself too). The bitter controvery was settle in Article IV of the Formula of Concord, which pointed out the excesses on both sides. Faith and good works (justification and sanctification) must not be confused in any way, but neither dare the importance of good works as an inevitable consequence of grace be minimized."In other words, the official Lutheran faith isn't simply mental assent to a set of doctrines, but rather a faith that is application oriented - Faith being the source, and works being the inevitable outcome.