Matthew 20:27 - Coke's Commentary on the Holy Bible

Let him be your servant— There is a gradation here not commonly observed: the original word διακονος in the former verse, which, for want of a better word, we rendered minister, is a name which might be given to any who occasionally attended others,or were statedly employed to render them any particular kind of service; but δουλος, servant, signifies one, whose whole business it is to serve, and who is indeed the property of another. Our Lord appears to mean, that he who presides over others, ought to consider his station, not so much a noble and high post, as a charge and office, which indispensably obliges him to be always ready to defend and assist his subjects. This may be an allusion to what is said, Deuteronomy 17:20 that the heart of the king of Israel ought not to be lifted up above his brethren; and generally, indeed, true greatness consists in a man's humbling himself, and condescending to the meanest and lowest offices, if hereby he can at all advance the true happiness of his fellow-creatures.