One verse

Bhagavad Gita 18.26

18.26

मुक्तसङ्गोऽनहंवादी धृत्युत्साहसमन्वितः | सिद्ध्यसिद्ध्योर्निर्विकारः कर्ता सात्त्विक उच्यते ||१८-२६||

muktasaṅgo.anahaṃvādī dhṛtyutsāhasamanvitaḥ . siddhyasiddhyornirvikāraḥ kartā sāttvika ucyate ||18-26||

mukta-saṅgaḥ
liberated from all material association
anaham-vādī
without false ego
dhṛti
with determination
utsāha
and great enthusiasm
samanvitaḥ
qualified
siddhi
in perfection
asiddhyoḥ
and failure
nirvikāraḥ
without change
kartā
worker
sāttvikaḥ
in the mode of goodness
ucyate
is said to be

One who performs his duty without association with the modes of material nature, without false ego, with great determination and enthusiasm, and without wavering in success or failure is said to be a worker in the mode of goodness.