Let us consider those who serve under our generals and the order, obedience, and submissiveness with witch they perform the things commanded them.  All are not prefects or commanders of a thousand, or of a hundred, or of fifty, or the like, but each one in his own rank performs the things commanded by the king and the generals.  The great cannot exist without the small, not the small without the great.  There is a kind of mixture in all things from which rises mutual advantage.  Take our body for example.  The head is nothing without the feet, and the feet are nothing without the head.  The very smallest members of our bodies are necessary and useful to the whole body, but all work harmoniously together and are under one common rule for the preservation of the whole body.  Let our whole body, then, be preserved in Christ Jesus, and let everyone be subject to his neighbor, according to the special gift bestowed upon him.  Let the strong not despise the weak, and let the weak show respect to the strong.  Let the rich man provide for the wants of the poor; and let the poor man bless God, because God has given him one to supply his need.  Let the wise man display his wisdom, not by words, but through good deeds.  Let us consider, then, brethren, of what matter we are made.

-Clement of Rome

Taken from Day by Day with the Early Church Fathers, page 155.