Delay enables escape and national victory

Servants wait at the locked doors until it is too late

When Ehud is gone, servants come, see the doors locked, and say he covereth his feet in his summer chamber, a euphemism for private relief or rest. They tarry till they are ashamed, then open with a key and find their lord fallen down dead. The delay is bodily and social. It is not a joke that makes bodily functions contemptible.

Escape becomes a trumpet, Jordan fords, and eighty years' rest

Ehud escapes to Seirath, sounds a trumpet in the mountain of Ephraim, and tells Israel to follow him, for the LORD has delivered their enemies the Moabites into their hand. They take the fords of Jordan toward Moab and suffer not a man to pass over. They slay about ten thousand, all lusty, that is stout, and all men of valour. Moab is subdued. The land has rest eighty years.

The private killing becomes national deliverance only when Ehud summons Israel and closes the crossings. The LORD is credited. The battle total and the eighty years are narrative figures, not an exact chronology or a policy for sealing modern borders with lethal force.