B.G 6.20,22, and 23

yatroparamate cittaṁ niruddhaṁ yogasevayā। yatra caivātmanā'tmānaṁ paśyannātmani tuṣyati ॥20॥

sukhamātyantikaṁ yattad buddhigrāhyamatīṁdriyam। vetti yatra na caivāyaṁ sthitaścalati tattvataḥ ॥21॥

yaṁ labdhvā cāparaṁ lābhaṁ manyate nādhikaṁ tataḥ। yasmin sthito na duḥkhena guruṇāpi vicālyate ॥22॥

taṁ vidyād duḥkhasaṁyogaviyogaṁ yogasañjñitam। sa niścayena yoktavyo yogo nirviṇṇacetasā ॥23॥

Where the mind is restrained by the practice of Yoga and stationed in the supreme, where indeed, seeing the lord through the mind, becomes satisfied within the body. The intellect perceives that supreme happiness which is beyond the senses, and understanding him as such doesn't vacillate from the situated true form of the Lord. Having achieved such a state, he considers no other gain as superior, and having situated there, is not disturbed by even the heaviest sorrow. Know that be Yoga which removes association or disassociation of misery, i.e. which allows one to transcend the misery. This yoga should be practiced with determination by one with a detached mind.

Gīta Bhāshya 6.20-23

'ātmanā' - by the mind; 'ātmani' - in the body; 'ātmānam paśyan' - seeing the Lord; 'tattvataḥ' - from the form of the Lord; 'duḥkhasaṁyoga viyogaḥ' - by which the connection with sorrow is separated, i.e. not only destroys the arisen sorrow but also prevents its very generation

ātmanā manasā। ātmani dehe। ātmānaṁ bhagavantaṁ paśyan। tatvataḥ bhagavadrupāta।॥20॥

The word 'ātmanā' means 'by the mind'; 'ātmani' means 'in the body'; 'ātmānam paśyan' means 'seeing the Lord'.

tatvataḥ bhagavadrupāta।॥21॥

The word 'tattvataḥ' means 'from the form of the Lord'.

duḥkhasaṁyogo yena viyujyate sa duḥkhasaṁyoga viyogaḥ। na kevalam utpannaduḥkhaṁ nāśayati, utpattimeva nivārayati iti darśayati saṁyogaśabdena। niścayena yoktavyaḥ yoktavya eva tadbubhūṣuṇā ityarthaḥ ॥23॥

That by which the connection with sorrow is separated, is the 'duḥkhasaṁyoga viyogaḥ'. It not only destroys the arisen sorrow but also prevents its very generation - is indicated by the word 'saṁyoga'. Indeed, it should be practiced with determination by the one who desires, is the meaning.

Gīta Tātparya 6.20-23

'ātmānam' - Lord Vishnu; 'ātmanā' - by His grace.

ātmānaṁ viṣṇum। ātmanā tatprasādena ॥20॥

The word 'ātmānam' refers to Lord Vishnu. The word 'ātmanā' means 'by His grace'.