"The Christian shoemaker does his Christian duty not by putting little crosses on the shoes, but by making good shoes, because God is interested in good craftsmanship."
- Quote widely attributed to Martin Luther
This doesn't mean that craftsmanship is the trump card for faithfulness at work. Surely there are exquisitely-made gambling tables and remarkable displays of artisanship in elite strip club furniture, but these are - in my opinion - misdirected uses of talent. Craftsmanship must be discerningly applied.
Of course, placing crosses on crappy shoes may be worse than applying craftsmanship to crappy ends, so maybe Luther is right in implying that we ought to start by making good shoes. That way, the little crosses (if we decide to put them on) are not cheap stamps of religious affiliation, but rather justification to customers for our excellence, and personal indicators that we would sell each shoe to God himself.
"So whether you eat or drink or whatever you do, do it all for the glory of God."
- From Paul to the church in Corinth, a city not unlike some of our own today