Bhagavad Gītā Chapter Four verse 22

yadṛcchālābhasaṃtuṣṭo dvandvātīto vimatsaraḥ |
samaḥ siddhāv asiddhau ca kṛtvā ’pi na nibadhyate ||

dvandva - pair of oppositessiddhi - accomplishment, performance, fulfilment, attainment, successmatsara - jealousy

Commentaries and Reflections

TKV Desikachar:

(Matsara or Jealousy)
To find fault in others.