We have a collection of 2 Jealousy quotes from Robert A Heinlein
"A competent and self-confident person is incapable of jealousy in anything. Jealousy is invariably a symptom of neurotic insecurity." (ID 8098)
"Love is that condition in which the happiness of another person is essential to your own... Jealousy is a disease, love is a healthy condition. The immature mind often mistakes one for the other, or assumes that the greater the love, the greater the jealousy." (ID 8160)