एषा ब्राह्मी स्थितिः पार्थ नैनां प्राप्य विमुह्यति। स्थित्वाऽस्यामन्तकालेऽपि ब्रह्मनिर्वाणमृच्छति ॥

eṣhā brāhmī sthitiḥ pārtha naināṁ prāpya vimuhyati sthitvāsyām anta-kāle ’pi brahma-nirvāṇam ṛichchhati

This is the Eternal state, O son of Prithâ. Having attained thereto, none is bewildered. Who, even at the death-hour, is established therein, he goeth to the Nirvâna of the Eternal.

In plain words: Krishna tells Arjuna that this is the eternal, divine state. Someone who reaches it is never confused again. If a person is settled in it even at the moment of death, they reach Nirvāna, final union with the Eternal.