Bhagavad-gītā As It Is · Text 5.20
Sense control, peace and inner happiness
न प्रहृष्येत्प्रियं प्राप्य नोद्विजेत्प्राप्य चाप्रियम् ।
स्थिरबुद्धिरसम्मूढो ब्रह्मविद्ब्रह्मणि स्थित: ॥ २० ॥
na prahṛṣyet priyaṁ prāpya
nodvijet prāpya cāpriyam
sthira-buddhir asammūḍho
brahma-vid brahmaṇi sthitaḥ
A person who neither rejoices upon achieving something pleasant nor laments upon obtaining something unpleasant, who is self-intelligent, who is unbewildered, and who knows the science of God is already situated in transcendence.
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