6:23  

तं विद्याद्‌दुःखसंयोगवियोगं योगसंज्ञितम् ।
स निश्चयेन योक्तव्यो योगोऽनिर्विण्णचेतसा ॥६- २३॥

Transliteration

taM widyaad‌duHkhasaMyogawiyogaM yogasaMdnyitam ।

sa nishchayena yoktawyo yogo'nirwiNNachetasaa ॥६- २३॥

Translation

Severance from union with sorrow by that knowledge is called yoga.
Concentrating on that yoga with certainty, enthusiastic concentration.

Translation

The (state of) severance of union with sorrow is known by the name of yoga. This yoga should be practiced with firm determination and perseverance, without any mental reservation or doubts.