Paul exhorts the people to regard their masters as worthy of all honour even if they were unbelievers. Those who serve believing masters, were encouraged to do much more because, those who benefit from their labours were believers, even though they now stand on equal footing as brethren.
In this generation, however we do not have people who serve as slaves anymore. But we have Christians who work for others. They may be employed to work in the homes of others or in their ventures. It is necessary for us as Christians to serve with utmost loyalty and honesty, so that the name of God which we bear may not be reviled.
In our time, going to work late and closing before time, using working hours for personal businesses, misusing the organization's resources and all manner of corrupt practices, are common features in the work place. How can we be salt and light when we are seen to be involved in things like these? It is time we reconsidered our ways and changed. If we are called to serve, we must do it well, as unto the Lord.