I am going to dive in and take the liberty of re-posting this here ... cause I think it goes (as the British say) 'swimmingly' ... although some may think it just 'all wet' ...
The Swimming Whole ...
Let me describe Shikantaza as like diving into an 'ol swimming hole ... a "swimming whole".
Sometimes, jumping into the waters of Shikantaza, I might feel like I'm just swimming freely and easily way far in the deep end. In fact, that "deep end" is so deep and vast that ... truly ... it does not seem limited at all by width or length or height or bottom or borders (so boundless and whole that even limited words like "deep" and "vast" cannot serve as a description). It might sound very very scary to swim there, as if one might easily lose one's bearings of "up" and "down" and "here" and "there" and "near" and "far" ... and thus DROWN! ... but it is not like that at all. One feels in one's natural home, a fish in water ... in fact, perfectly 'waterfish' ... and a swimmer can 'lose himself' there (in a very good way) and swim freely and effortlessly in all directions. In fact, if one gets really really really deep beyond sight of the shore ... one can experience sometimes that there is no "I" who is a "swimmer" with arms and legs forging ahead in some "water" ... no "place to go" or "time" ... and all is just flowing flowing.flowing effortlessly and naturally. Perhaps it is much like an unborn infant floating peacefully in the womb ... the infant even without thought of itself vs. mother, of up and down, inside and outside, of birth.
The other end of the "swimmin' hole" is shallow and hot, most folks spend their life there, and it makes a very crowded beach. Folks bump into one another and often feel cramped and lacking, constantly looking at their watches and hoping for something better. They must head again and again to the over priced concession stands to stuff themselves with junk. They almost cannot find the water amid the plastic trash and oil spills, and are lost in searching for it. When they encounter it, most are afraid to jump in.
(In fact, the "deep" water is so all encompassing and boundless, that it fully holds the shallow end too, and everything else ... All is just the "swimming whole", but the shallow folks usually cannot sense that). Our Shikantaza practice is something like jumping in that water and allowing the current to take us to the deep end.
Got the image?
Okay, here's my point:
Sometimes, in Zazen, we get really really deep ... to the "no swimmer, no water, no time" part. That's good!
But most days, we are somewhere in between "shallow" and "deep" ... which is good too! One reason is because we come to realize that the "shallow" -is- the "deep" too, just "the deep" in the shallow part close to shore! Also, the shallow part is where life happens, and one cannot really have a life if only out in the deep end. Thus, our real practice is to learn to swim around the shallow end or play up on the beach, and still feel the freedom of the water all around. Something like that.
Some types of Buddhism and other Eastern philosophies will tell you that the only point of practice (or meditation) is to get into the really really really deep part. They claim that everything in the shallow end is a lie, or "delusion", so we must get away from the shallow. Even some schools of "Zen" will emphasize something like that ... that the "real" is only when we are in the very very deep water far away from shore.
But I do not feel so. I feel that our practice is to sometimes be in the deep water, sometimes in the middle water or shallow water, sometimes frolicking on the beach ... but feeling up to our gills that it is all the "boundless water" and we are always swimming free all the time (even when, as often happens, we cannot always feel free, or wet, or even damp). Thus, we realize, that the shallow is not "shallow" at all, and is in fact the deep water whole (i.e., delusion is not just "delusion", samsara is not just samsara etc.). Our view and experience of the beach and shore is transformed into something very different (although the same old crowded beach too ... with its junk food to avoid and oil spills to clean up ... despite being also all Healthy and Clean from the start).
So, for that reason, I do not think that the only "good Zazen" is very very deep Jhana states or earth shattering Kensho and the like. Sometimes that is good. It may even be necessary in our practice to get out there from time to time. But, ultimately, shallow swimming is good, deep swimming is good, in between swimming is good ... so long as we learn, through Shikantaza, that it is all deep, all "whole", all beyond "deep or shallow", there is no place we need go, no time to get there.
In that, we keep on swimming swimming swimming energetically and moving ahead in life ... even though we are always up to our necks in the H2O, and there is no place to go that's not soaking wet. Something like that.
By the way, how do we "find the water" in Shikantaza? Why, by giving up the distant search ... by being still ... thus to find that we were bathing in it, and were it, all along! Then, we cast out our arms ... drop all resistance ... merging into the stream ... allowing the current to carry us where it will. Deep "Shikantaza" is good swimming, shallow "Shikantaza" is good swimming ... all is good swimming.
Something like that. A swimming whole.