Ephesians 6:5-8

5Slaves, obey your earthly masters with respect and fear and sincerity of heart, just as you would obey Christ. 6And do this not only to please them while they are watching, but as servants of Christ, doing the will of God from your heart. 7Serve with good will, as to the Lord and not to men, 8because you know that the Lord will reward each one for whatever good he does, whether he is slave or free.