B.G 18.51-55

buddhyā viśuddhayā yukto dhṛtyā''tmānaṃ niyamya ca। śabdādīn viṣayāṃstyaktvā rāgadveṣau vyudasya ca ॥51॥

viviktasevī laghvāśī yatavākkāyamānasaḥ। dhyānayogaparo nityaṃ vairāgyaṃ samupāśritaḥ ॥52॥

ahaṅkāraṁ balaṁ darpaṁ kāmaṁ krodhaṁ parigraham। vimucya nirmamaḥ śānto brahmabhūyāya kalpate ॥53॥

brahmabhūtaḥ prasannātmā na śocati na kāṅkṣati। samaḥ sarveṣu bhūteṣu madbhaktiṃ labhate parām ॥54॥

bhaktyā mām abhijānāti yāvān yaś cāsmi tattvataḥ। tato māṁ tattvato jñātvā viśate tad-anantaram ॥55॥

With intellect purified, engaged with determination, controlling oneself, and abandoning sensory objects like sound, one discards attachment and aversion; one who enjoys solitude, is a moderate eater, controlled in speech, body, and mind, is always devoted to meditation and yoga, and has fully embraced dispassion; having abandoned ego, strength, pride, desire, anger, and possessiveness, and who is free from the sense of ownership and is peaceful, is eligible to attain the state of abiding in Brahman. A person who is realized in Brahman, with a pleased mind, neither laments nor desires anything. Being equally disposed to all beings, such a person attains My supreme devotion. Through devotion, he knows me, how much and who I am in reality. Then, having known me in reality, he enters that afterwards.

Gīta Bhāshya 18.51-55

'brahmabhūyāya' - being in a constant state of mindfulness and abiding in Brahman.

brahmabhūyāya kalpate - brahmaṇi bhāvaḥ brahmabhūyam। brahmaṇi sthitiḥ। sarvadā tanmanaskatetyarthaḥ ॥53॥

In the term 'brahmabhūyāya kalpate', 'brahmabhūyāya' means the state of being in Brahman; it means being in a constant state of mindfulness and abiding in Brahman.