Jamieson, Fausset and Brown on 2 Kings 5:27

27. leper as white as snow--(See on Le 13:3). This heavy infliction was not too severe for the crime of Gehazi. For it was not the covetousness alone that was punished; but, at the same time, it was the ill use made of the prophet's name to gain an object prompted by a mean covetousness, and the attempt to conceal it by lying [Keil].