“Become such as you are, having learned what that is”
Pythian 2, line 72.
Variant translations:
Be what you know you are
Be true to thyself now that thou hast learnt what manner of man thou art
Having learned, become who you are
Original
γένοι' οἷος ἐσσὶ μαθών
Help us to complete the source, original and additional information
Pindar 13
Ancient Greek poet -517–-437 BCRelated quotes

Speaking to a Senate Committee in 1987, as quoted in the Guardian Weekly, November 4, 2005.
1980s

“Reviewing what you have learned and learning anew, you are fit to be a teacher.”
Source: The Analects, Chapter II

Source: Samson after hitting a century on 2017 Indian Premier League about his unsuccessful domestic season. Sanju Samson says bad times taught him a lot https://m.economictimes.com/news/sports/sanju-samson-says-bad-times-taught-him-a-lot/amp_articleshow/58144832.cms

“When asked what learning was the most necessary, he said, "Not to unlearn what you have learned."”
Antisthenes, 4.
The Lives and Opinions of Eminent Philosophers (c. 200 A.D.), Book 6: The Cynics

“You make do with what you have. As you age you learn even to be happy with what you have.”
Source: What I Talk About When I Talk About Running