Imam As-Sadiq (a.s) said:
"الحاسِدُ مُضِرُّ بِنَفْسِهِ قَبْلَ أَنْ يُضُرّ بِالْمَحْسُودِ"
An envious person sustains a loss to himself before causing a loss to the one he envies.1
The spirit of envy refers to not tolerating others enjoying a blessing, and trying to deprive them from that blessing, or causing a loss to them in other ways.
An envious person’s tendency is to act as a destructive force , seeking failure of others, rather than a constructive force that seeks one’s own improvement and success.
Envy is a severe moral disease . Psychologists assert that feelings of resentment and jealousy harbored by the envious persons play havoc with their emotional and physical health and their actions bring suffering and humiliation only to themselves. It is far better to concentrate on one’s own success as opposed to trying to hold others back .