With the exception of the last one (although arguably it was, but mostly it was posted becasause a) I wanted to learn what Dogen's name was in kanji, and b) it's a good thing to remember what Dogen said on studying one's self), the posts in the past day or two have been about Joshu's Dog. Actually not about Joshu's Dog, they've been Joshu's Dog.
While this koan can have many meanings imparted to it, there is one specific meaning that is taken to be "passing" this koan. The use of the terms "passing" and "meaning" here is quite interesting, because it is probably unique usages of those terms.
The "answer" given to the koan, as the Westerners after WWII noted out of their anthropological curiosity about the Japanese and Zen, was not so much a rote answer as it is a way of being. In fact, the "answers" to the koans are supposedly widely known, and have been published in English and Japanese. But reading the answers will do you no good in sanzen or dokusan, if you've got any kind of a "teacher" who is properly deeply realized himself.
And this is ultimately why we practice Zen: to have the true freedom to have a very particular way of being. When you have this freedom, every word that koan Joshu's dog (interestingly translated by Google from Chinese as "son of a bitch") makes perfect sense. If you have no awareness that such a freedom can exist, it looks almost like sentences generated at random. "What the hell is up with that hot iron ball stuff anyway? " you might ask. Who the heck is this "General Kuan" (as it appears in some versions of the koan)? Why would I want to kill the Buddha?
I could go on ad nauseum, but suffice it to say that in this very particular way of being , suffering may be transcended. But it ain't static for nobody.