a double-edged sword

something that causes both advantages and problems His great intelligence was a real double-edged sword because he never felt he could communicate with ordinary people.

Common Names:

Name	Pronounced	Usage
Amann	['æmən]
Tarquinius	-	Ancient Roman
Elihu	i-LIE-hyoo (English), ee-LIE-hyoo (English)	Biblical, Biblical Hebrew, English (Archaic)
ÉAmonn	AY-mon	Irish
China	CHIE-nə	English (Modern)
Mordad	-	Persian Mythology