The country's leaders have been trying to 'muster' (up) support for the war.
His cooking could 'pass muster' in an expensive French restaurant.
These excuses will not 'pass muster'. [=they are not acceptable]
(..) That is why it is critical to strike soon while the victor still licks his wouns. Surely your Uncle Kevan coul muster a force. My Uncle Kevan has all the courage of a kitchen mouse. Ser Jaime, then. Jaime's away on a sensitive iplomatic mission. (..)2015 TvShow: Game of Thrones Title: Unbowed, Unbent, Unbroken Season: 5 Episode 6