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."