What degree of force is permissible when striking an intruder?

Primary text

The house owner is prohibited from striking the watcher with something intended to kill them outright. If the striker uses a stone capable of killing or a heavy piece of metal, they are liable for retaliation (Qisas). This is because the permission granted is only to remove the offending sight causing the harm, not to inflict harm beyond that. If deterrence with a light object fails, it is permissible to strike with a heavier object until the intruder is repelled. This applies whether the watcher is on the public road, in one's own property, or elsewhere.