You may have heard reference to the word "zen." You may also have heard reference to the word "zazen." What is the difference? Uh... "zazen" is German. Enough with these foolish questions.
The koan: "A Mother's Advice"
Jiun, a Shingon master, was a well-known Sanskrit scholar of the Tokugawa era. When he was young he used to deliver lectures to his brother students.
His mother heard about this and wrote him a letter:
"Son, I do not think you became a devotee of the Buddha because you desired to turn into a walking dictionary for others. There is no end to information and commentation, glory and honor. I wish you would stop this lecture business. Shut yourself up in a little temple in a remote part of the mountain. Devote your time to meditation and in this way attain true realization."
The enlightenment: No, shut YOURself up in a little temple in a remote part of the mountain, MOM.
This has been "Zen Koans Explained." The way a horse walks.