On two occasions Paul gives specific instructions for Christians who are slaves (douloi). In both instances (Colossians 3:22; Ephesians 6:5) he urges them to engage their responsibilities “with sincerity of heart” (en haplotēti kardias), fearing (or reverencing) the Lord (Colossians), or as they “would obey Christ” (Ephesians), as translated in the New International Version (NIV). [...]