Thanks for the link, tsuwm. The version "they protect me" makes good sense. The shepherd's crooks I have seen have a U-shaped end that can be used to catch sheep by neck to restrain it with out hurting it. It might be damaged trying to drive away a predator, for which a sturdy club would be needed. I wonder when sheep dogs were first used. I don't remember their being mentioned in the Bible.

I found a site that stated dogs were domesticated by 10,000 BC, and sheep by 8,000 BC. From the very beginning a domesticated dog could warn of approaching predator, which would be very valuable. I seem to remember reading somewhere that the use of dogs for herding sheep is comparatively recent.