"A sound heart is life to the flesh, But envy is rottenness to the bones."
- Bible: Proverbs 14:30 New King James Version (NKJV)
"Envy is rottenness to the bones" means that a resentful and discontented attitude of envy is destructive and corrupting to a person's entire being, both spiritually and physically. The metaphor illustrates how envy eats away at a person's health and inner strength, causing a slow, internal decay that diminishes joy and leads to self-destruction.
- From online source with editing
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Difference between envy (妒忌) and jealousy (嫉妒）:
- Envy is wanting what someone else has;
- Jealousy is when one worries someone will take what
1. one has or
2. one thought one had or
3. one could have had.
I believe one should treasure what one already has and work hard to achieve what one desires, if possible. There is no need to envy anyone, as it will be a waste of one's time, in addition to what stated above.
So if one cares, be happy for others when others show good qualities and are successful; If one doesn't care, just be happy with oneself.
Have a good Tuesday. 
