When a mean wretch cannot vie with another in virtue, out of his wickedness he begins to slander. The abject envious wretch will slander the virtuous man when absent, but when brought face to face his loquacious tongue becomes dumb.
SaadiWhen you see contention amongst your enemies, go and sit at ease with your friends; but when you see them of one mind, string your bow, and place stones upon the ramparts.
Saadi