Proverbs 27:4 - Matthew Poole's English Annotations on the Holy Bible

Envy is worse than both of them, partly, because it is more unjust and unreasonable, as not caused by any provocation, as wrath and anger are, but only proceeding from a malignity of mind, whereby a man is grieved for another man's happiness, in which he should rejoice; partly, because it is more deeply rooted and implacable, whereas the other passions are commonly allayed; and partly, because it is more secret and undiscernible, and therefore the mischievous effects of it are hardly avoidable; whereas wrath and anger discover themselves, and so forewarn and forearm a man against the danger.