Also,
throw the first stone. Be quick to blame, criticize, or punish, as in
She's always criticizing her colleagues, casting the first stone no matter what the circumstances . The term comes from the New Testament (John 8:7), where Jesus defends an adulteress against those who would stone her, saying "He that is without sin among you, let him first cast a stone at her." Also see
people who live in glass houses;
pot calling the kettle black.