The head of each of the major Japanese tea schools (the Sen Sanke � 三家) is also a Zen buddhist abbot, and in Japan, the tea ceremony 茶事 is also considered a religious ceremony. Yet, in my study of it I have found nothing that is overtly religious that ties it specifically to buddhism. Yes, it is desgined with buddhist and shinto principles in mind, but not in any way that would exclude the happy participation of Christians or Muslims. In fact, three of great tea master, Sen Rikyū's students were Christian. It is not now unheard of for tea to be offered in Japanese churches (kencha �茶) in the same way that it has traditionally been offered in buddhist temples and in Shinto shrines.
I spent the last two days studying the ceremony from Jennifer Anderson's vivid book, and it seems apparent that tea is actually of quite cursory importance to the Japanese "tea" ceremony. Of utmost importance is instead the complex interplay between host and guest that unfolds like an elaborate inside joke. The setting, calligraphy, flowers, each and every utensil will be chosen with a specific meaning or theme in mind (the toriawase å�–å�ˆã�›). For example, if the host is the former teacher of the guest and the ceremony takes place in October, then the tea scoop used for that occasion may be called Sottaku DÅ�ji å�’å•„å�Œæ™‚, which the guest recognises as a quotation from the Hekigan Roku: the quotation refers to the intuition of a mother bird which starts to peck at an egg shell at precisely the same time as its hatching chick, and this represents the sudden spontaneous understanding of student and teacher. The feather of a wild goose may be laid across the charcoal basket, with the intent of evoking autumn in the mind of the guest. The sweets may be made in the shape of autumn leaves. The rôle of host is to design the ceremony with a theme and his guest in mind; the rôle of the guest is to seek out and to appreciate each of dozens of references hidden in the ceremony. This is the essential reason why it is not possible for uneducated foreigners to take part in the Japanese tea ceremony: they just would not get the point. For this reason, the tea ceremony takes a minimum of 10 years to learn: it does not take that long to learn how to make tea, but it takes that long to learn to recognise and to select from the hundreds of variations, hidden meanings and symbols that are part of the ceremony.
Anderson, Jennifer L. (1991) An Introduction to Japanese Tea Ritual. Albany, New York: State University of New York Press. ISBN: 0-7914-0750-0.