Did Harbhajan Singh Yogi say
If you want to learn something - read about it; understand something - write about it; master something - teach it.
Wikiquote has it as unsourced, and there's an unsourced claim that a variant, "To learn, read. To know, write. To master, teach." is a Hindu proverb.
The quote is noted on the official site that publishes and certifies on his behalf,
“If you want to learn something, read about it.
If you want to understand something, write about it.
If you want to master something, teach it.”
—Yogi Bhajan
(see the bottom of that page)
If this is implied in other ways in older texts that remains to be confirmed.
