Judges 3:12-16

Now the sons of Israel again did evil in the sight of the Lord. So the Lord strengthened Eglon the king of Moab against Israel, because they had done evil in the sight of the Lord.

And he gathered to himself the sons of Ammon and Amalek; and he went and defeated Israel, and they took possession of the city of the palm trees.

And the sons of Israel served Eglon the king of Moab for eighteen years. Ehud Kills Eglon

But when the sons of Israel cried out to the Lord, the Lord raised up a deliverer for them, Ehud the son of Gera, the Benjaminite, a left-handed man. And the sons of Israel sent tribute by him to Eglon the king of Moab.

Now Ehud made himself a sword which had two edges, a cubit in length, and he strapped it on his right thigh under his cloak.