Ephesians 6:5-6

5 Slaves, obey your earthly masters with respect and fear, and with sincerity of heart, just as you would obey Christ.

6 Obey them not only to win their favor when their eye is on you, but as slaves of Christ, doing the will of God from your heart.

Ephesians 6:9

9 And masters, treat your slaves in the same way. Do not threaten them, since you know that he who is both their Master and yours is in heaven, and there is no favoritism with him.