legendary formula, thought to hold its origins in 13th century Europe. As the tale goes, four thieves managed to successfully rob their plague-ridden neighbors and avoid the illness. When caught and questioned, they sold the secret formula for their lives; and so it has passed down to modern magical usage for healing, health , and protection, as well as an important component in many banishing spells.
 

Carmin's Extended Notes on Four Thieves Vinegar

        Add to the bath to increase health and vitality, break hexes, purify, and protect from illness and magical attack. Wonderful in all healing rituals. Place a bowlful under your bed during illness to speed recovery. Traditionally used to protect yourself from an enemy; sprinkle across their doorstep, toss a bit in their vicinity. It need not make physical contact.
Use as a natural cleanser and floor wash. Insect repellant, in both the magical and mundane senses!