Bhagavad Gita 4.22
Content with what comes to him without any effort of his own, rising above the pairs of opposites, free from envy, his mind balanced in both success and failure; though he acts, the consequences do not bind him.
यदृच्छालाभसन्तुष्टो द्वन्द्वातीतो विमत्सरः।
समः सिद्धावसिद्धौ च कृत्वापि न निबध्यते॥yadṛcchālābhasantuṣṭo dvandvātīto vimatsaraḥ|
samaḥ siddhāvasiddhau ca kṛtvāpi na nibadhyate||
English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).