cast the first stone

From the Bible John 8.7 where Jesus tells the accusers of a woman of adultery, He that is without sin among you, let him first cast a stone at her.

• Audio (AU)

  (file)

cast the first stone

1. (idiomatic) To act self-righteously in accusing another person, believing oneself to be blameless.
   • 2007, March 10, Mr Gingrich, on the impeachment proceedings in 1999. Reported in The Guardian

     I knew I couldn't cast the first stone as I knew I had weaknesses. ... (But) as a leader of the government trying to uphold the rule of law I have no choice but to move forward and say you cannot accept perjury in your highest officials.