As the creator and sustainer of the universe He deserves the best of what we are. After all, He created us and gave us the talent we have. If we are making a presentation for our work, we give it all that we have. Shouldn't we approach assignments like teaching a Sunday school class or leading a Bible study, or meeting one on one to encourage another believer the same way?
Sometimes I have felt like mailing it in, just coasting through the assignment. After all it is only church.