(Translated from here)
Translated by Judit Simon
Tea ceremony is not only closely related to zen buddhism, but it also takes its roots in it.
It originates from the tea-drinking gatherings of Japanese monks who, before taking their tea, made offerings to various deities. Zen buddhist monks became the first tea masters and the Japanese tea ceremony began to evolve its own aesthetic. Tea ceremony dates back to the 15th-16th century when Japanese masters like Murata Shukō (村田珠光, 1423-1502 C.E.) or Sen no Rikyū (千利休, 1522-21 April, 1591) perfected the art of tea-drinking, developing it into a fully spiritual practice.
A tea master aspires to be more than an artist - he wishes to become one with his art. The aim is to reach total unity. A tea master becomes one with his art like a zen archer becomes one with his target. There is no clear boundary between the mind and the hand, action and non-action
This amazing art is described in full detail in the Book of Tea by Okakura Kakuzō (岡倉覚三, also called: Okakura Tenshin, 岡倉 天心 14 February 1862.- 2 September 1913. C.E). Tea ceremony still preserves the harmony and art its masters established hundreds of years ago.
Calligraphy plays a central role in tea ceremonies. The only decoration a sparsely furnished tearoom usually allows for is a piece of carefully chosen calligraphy, and, occassionally, a Japanese flower-arrangement (ikebana, 生け花).
Since Zen masters create their calligraphy masterpieces in a state of "no-mindedness" (a state where the mind flows freely and ultimate concentration can be attained), their works are fresh and original, full of vital energy. Master Sen no Rikyū believed that a tea-room should be decorated with nothing else but a piece of calligraphy. He was certain that only the kind of art that truly reflects the vitality of zen can lead the mind towards enlightenment.. He realized that calligraphy inevitably followed high-level spirituality. A perfect brush stroke can only be drawn with a hand led by a compassionate mind. A calligraphy that reflects deep thoughts cannot be created with a wandering mind filled with superficial ideas..A kanji that can reveal its innermost meaning to the viewer must be written by a master who has attained oneness of mind through meditation and understanding.
Here is a calligraphy I have made for a friend's tearoom. It is a well-known phrase, an invitation for tea.