Colossians 3:22-4:1

22 Slaves, obey in everything those who are your earthly masters, not by way of eye-service, as people-pleasers, but with sincerity of heart, fearing the Lord. 23 Whatever you do, work heartily, as for the Lord and not for men, 24 knowing that from the Lord you will receive the inheritance as your reward. You are serving the Lord Christ. 25 For the wrongdoer will be paid back for the wrong he has done, and there is no partiality.

4:1 Masters, treat your slaves justly and fairly, knowing that you also have a Master in heaven. (ESV)