Judges 3:14-16

And the Israelites served Eglon of Moab for eighteen years. But when the people of Israel cried out to the LORD for help, the LORD again raised up a rescuer to save them. His name was Ehud son of Gera, a left-handed man of the tribe of Benjamin. The Israelites sent Ehud to deliver their tribute money to King Eglon of Moab. So Ehud made a double-edged dagger that was about a foot long, and he strapped it to his right thigh, keeping it hidden under his clothing.