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न प्रहृष्येत्प्रियं प्राप्य नोद्विजेत्प्राप्य चाप्रियम् ।
स्थिरबुद्धिरसंमूढो ब्रह्मविद्ब्रह्मणि स्थितः ॥५- २०॥

na prahRRiShyetpriyaM praapya nodwijetpraapya chaapriyam ।

sthirabuddhirasaMmooDho brahmawidbrahmaNi sthitaH ॥५- २०॥

Source: Automatic ITRANS Transliteration

Not delighting in receipt of the desired, not grieving in receipt of the undesired,

Steady-thinking, unconfused, knowing Brahma, is established in Brahman.

Source: Milind S. Pandit

One who neither rejoices on obtaining what is pleasant nor grieves on obtaining the unpleasant, who is undeluded, who has a steady mind, and who is a knower of Brahman; such a person abides in Brahman.

Source: The Bhagavad-Gita: The Sacred Song

A person who neither rejoices upon achieving something pleasant nor laments upon obtaining something unpleasant, who is self-intelligent, unbewildered, and who knows the science of God, is to be understood as already situated in Transcendence.

Source: Bhagavad Gita As It Is