Trust no one until you are very sure of the heart to which you open your heart.
 Honoré de Balzac, Father Goriot (1835). copy citation

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Author Honoré de Balzac
Source Father Goriot
Topic trust heart
Date 1835
Language English
Reference
Note Translated by Ellen Marriage
Weblink http://www.gutenberg.org/files/1237/1237-h/1237-h.htm

Context

“Yet, if you have a heart, lock it carefully away like a treasure; do not let any one suspect it, or you will be lost; you would cease to be the executioner, you would take the victim’s place. And if ever you should love, never let your secret escape you! Trust no one until you are very sure of the heart to which you open your heart. Learn to mistrust every one; take every precaution for the sake of the love which does not exist as yet. Listen, Miguel”—the name slipped from her so naturally that she did not notice her mistake—“there is something still more appalling than the ingratitude of daughters who have cast off their old father and wish that he were dead, and that is a rivalry between two sisters.” source