Bhagavad Gita 6.23 Chapter 6, Verse 23

तं विद्याद् दुःखसंयोगवियोगं योगसंज्ञितम् ।
स निश्चयेन योक्तव्यो योगोऽनिर्विण्णचेतसा ॥६.२३॥

taṃ vidyād duḥkhasaṃyogaviyogaṃ yogasaṃjñitam
sa niścayena yoktavyo yogo'nirviṇṇacetasā

Meaning

know that state, the breaking of contact with sorrow, to be yoga. This yoga should be practised with determination and an undaunted mind.

Newly written by Bhajan Dhun — scholarly review in progress.

Reference: Bhagavad Gita 6.23 (Chapter 6, The Yoga of Meditation (Atma Samyama Yoga), Verse 23)