But in today's world of flight, you can't use just any locks on your bags while flying, they need to be the type that TSA can open as needed (without destroying the lock). These approved locks are designated by the red diamond symbol you see on the upper right corner of the photo here.
If you have other locks, you could throw a couple inside your suitcase to use in the hotel rooms.
And speaking of hotels, many do NOT provided washcloths. So, maybe you want to throw an old one in your suitcase (and toss it at the end of the trip to have *that* much more space for souvenirs), or a mesh sponge that squishes down to just about nothing.
What about electricity? Well if you are only concerned about recharging your camera or smart devices, you will only need to get an adapter (so that the plug shape will match correctly), you would not need a converter (that switches power voltage). IF you want to bring a hair dryer or curling iron, THEN you would need a converter- but most hotels will have hair dryers in the room. (It is possible that the one in Galilee might not, but... all will be well!)