"Subjecting yourselves one to another," he says, "in the fear of Christ." For if thou submit thyself for a ruler's sake, or for money's sake, or from respectfulness, much more from the fear of Christ. Let there be an interchange of service and submission. For then will there be no such thing as slavish service. Let not one sit down in the rank of a freeman, and the other in the rank of a slave; rather it were better that both masters and slaves be servants to one another;--far better to be a slave in this way than free in any other; as will be evident from hence. Suppose the case of a man who should have an hundred slaves, and he should in no way serve them; and suppose again a different case, of an hundred friends, all waiting upon one another. Which will lead the happier life? Which with the greater pleasure, with the more enjoyment? In the one case there is no anger, no provocation, no wrath, nor anything else of the kind whatever; in the other all is fear and apprehension. In the one case too the whole is forced, in the other is of free choice. In the one case they serve one another because they are forced to do so, in the other with mutual gratification. Thus does God will it to be; for this He washed His disciples' feet.
John Chrysostom, Homily XIX on Ephesians