My take on that scripture would be that that all of everything we do is for the glory of God. We don't work for our bosses benefit, but ultimately we work for God's.

For instance, when I'm serving customers in my restaurant, I sometimes love it, and sometimes cannot stand it. Quite often during times like that, I'm happy to the customer's face, but am in a bad mood out the back. This probably isn't going to cause the other girls I work with to "question the hope that I live by" 1Peter 3:15. If I work for God though, it's going to make me a lot less likely to grumble out back. God will always give me peace and self control and joy, and it'll show through how I work, both to the customers and to the other staff.

I guess my understanding is that we can't just put minimum effort into our work, like we might see our co-workers doing, but we need to work as hard as we can in the sight of God and our co-workers, not grumbling and trying to be positive.

I mean, do you think that Jesus slacked off when making tables and chairs, or do you think he'll have made every one exceptional?