Bonhoeffer on vocation

Bonhoeffer's book The Cost of Discipleship is now on my summer ordering list. I need grace, and I also need to understand it in a way that will make me stop sinning and change the way I work. Bonhoeffer goes through me like the north wind in that regard.

Dietrich Bonhoeffer, Works Vol. 4: Discipleship (Green & Krauss tr.), Fortress, 2001. p. 49

For Luther, on the contrary, a Christian's secular vocation is justified only in that one's protest against the world is thereby most sharply expressed. A Christian' secular vocation receives new recognition only to the extent that it is carried on while following Jesus.