“Don't ask for what you'll wish you hadn't got.”
Seneca himself states that he is quoting a 'common saying' here.
Alternate translation: Do not ask for what you will wish you had not got. (translator unknown).
Source: Epistulae Morales ad Lucilium (Moral Letters to Lucilius), Letter XCV: On the usefulness of basic principles, Line 1
Original
postea noli rogare quod inpetrare nolueris.
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Seneca the Younger 225
Roman Stoic philosopher, statesman, and dramatist -4–65 BCRelated quotes

"Looking For Your Own Face" as translated by Coleman Barks in The Hand of Poetry: Five Mystic Poets of Persia
Context: Don't be dead or asleep or awake.
Don't be anything.
What you most want,
what you travel around wishing to find,
lose yourself as lovers lose themselves,
and you'll be that.

I Will Possess Your Heart
Narrow Stairs (2008)

Spoken before the performance of Only A Lad from Oingo Boingo's farewell concert on October 31, 1995 (which was released on CD, VHS and DVD).

Letter to Me, written by Brad Paisley.
Song lyrics, 5th Gear (2007)