Christianity does not apply to the mundane duties of life

(J.R. Miller)

"Whatever your hand finds to do — do it with all your might!" Ecclesiastes 9:10

Christ never asks for anything which we are not able to do. But let us not forget, that He always expects and requires of each of us, the best that we can do. The faithfulness which Christ wants and approves, implies the doing of all our work, our business, our trade, our daily toil — as well as we can.

Let no one think that Christianity does not apply to the mundane duties of life. It applies to the way you do your most common work — just as really as to your praying and keeping of the commandments. Whatever your duty is, you cannot be altogether faithful to God, unless you do your best. To slur any task, is to do God's work badly. To neglect it, is to rob God.
The faithfulness which Christ requires, must reach to everything we do. It impacts the way . . .
  the child learns his lessons and recites them,
  the dressmaker and the tailor sew their seams,
  the blacksmith welds the iron, and shoes the horse,
  the plumber puts in his pipes,
  the carpenter builds the house,
  the clerk represents the goods, and measures or weighs them.

How soon would genuine Christian living put a stop to all dishonesty, all fraud, all skimping, all false weights and measures, all shams, all neglects of duty — if this lesson were only learned and practiced everywhere!

"So whether you eat or drink or whatever you do — do it all for the glory of God!" 1 Corinthians 10:31