Bhagavad Gita: Chapter 2, Verse 71

विहाय कामान्यः सर्वान्पुमांश्चरति निःस्पृहः ।
निर्ममो निरहङ्कार स शान्तिमधिगच्छति ॥ २-७१ ॥

vihāya kāmān yaḥ sarvān pumāṁś carati niḥspṛhaḥ
nirmamo nirahaṅkāraḥ sa śāntim adhigacchati 2.71

A person who has given up all desires for sense gratification, who lives free from desires, who has given up all sense of proprietorship and is devoid of false ego – he/she alone can attain real peace.