I have often heard people say that “meditation is focusing and concentrating on one thing so intently you exclude all else.” This also ties in a little with a post I saw around what we should focus on during zazen. Jundo has made mention of the several parts of the body that some teachers suggest you focus on, some the spine, some the hands, most the breath. I think it is important to remember that these are just aids to assist in the development of your zazen practice. Much like the words, symbols, allegories and metaphors that we use when we talk about Zen practice, a practice “beyond words”, assist us on our never-ending journey to realize our Buddha-nature.
I think that zazen is “ focusing on “One” thing so intently that you include all else.”