There follows then what? All your might and all your thought of iniquity all the day, and meditation of malignity in your tongue without intermission, has performed what, done what? "As with a sharp razor you have done deceit" [Psalm 52:3]. See what do evil men to Saints, they scrape their hair. What is it that I have said? If there be such citizens of Jerusalem, that hear the voice of their Lord, of their King, saying, "Fear not them which kill the body, but are not able to kill the soul:" that hear the voice which but now from the Gospel has been read, "What does it profit a man, if he shall gain the whole world, and of himself make wreck:" [Matthew 16:26] they despise all present good things, and above all life itself. And what is Doeg's razor to do to a man on this earth meditating on the kingdom of heaven, and about to be in the kingdom of heaven, having with him God, and about to abide with God? What is that razor to do? Hair it is to scrape, it is to make a man bald. And this belongs to Christ, who in the Place of a Skull was crucified. [Matthew 27:33] It makes also the son of Core, which is interpreted baldness. [1 Chronicles 6:22] For this hair signifies a superfluity of things temporal. Which hairs indeed are not made by God superfluously on the body of men, but for a sort of ornament: yet because without feeling they are cut off, they that cleave to the Lord with their heart, so have these earthly things as they have hair. But sometimes even something of good with "hair" is wrought, when you break bread to the hungry, the poor without roof you bring into your house; if you shall have seen one naked, you cover him: [Isaiah 58:7] lastly, the Martyrs themselves also imitating the Lord, blood for the Church shedding, hearing that voice, "As Christ laid down His life for us, so also ought we also to lay down for the brethren," [1 John 3:16] in a certain way with their hair did good to us, that is, with those things which that razor can lop off or scrape. But that therefore even with the very hair some good can be done, even that woman a sinner intimated, who, when she had wept over the feet of the Lord, with her hair wiped what with tears she wetted. [Luke 7:38] Signifying what? That when you shall have pitied any one, you ought to relieve him also if you can. For when you have pity, you shed as it were tears: when you relieve, you wipe with hair. And if this to any one, how much more to the feet of the Lord. The feet of the Lord are what? The holy Evangelists, whereof is said, "How beautiful are the feet of them that tell of peace, that tell of good things!" Therefore like a razor let Doeg whet his tongue, let him whet deceit as much as he may: he will take away superfluous temporal things; will he necessary things everlasting?
[AD 430] Augustine of Hippo on Psalms 52:3