BG Chap 18 - The brahma-bhūta platform

One situated on that platform, having realized the soul, becomes joyful, and does not lament nor hankers for anything except the Lord. He looks upon all beings as equal. In that state he attains pure bhakti toward Kṛṣṇa. To the impersonalist, achieving the brahma-bhūta stage, becoming one with the Absolute, is the last word. But for the personalist, or pure devotee, one has to go still further, to become engaged in pure devotional service. This means that one who is engaged in pure devotional service to the Supreme Lord is already in a state of liberation, called brahma-bhūta, oneness with the Absolute. Without being one with the Supreme, the Absolute, one cannot render service unto Him. When one realizes his ātmā, and thus becomes situated in the brahma-bhūta platform, he is free from the contamination of the guṇas. Because of absence of misconceptions of the body, when he loses something, he does not lament, and when he fails to attain something, he does not hanker for it. Like an innocent child, he regards all beings as equal whether good or bad. He considers all entities, high or low, other than the Supreme Lord, to be equal. At this stage, one attains paraṁ bhakti. This is confidential knowledge as explained by the Lord.

After attainment of the brahma-bhūta stage of freedom from material conceptions, devotional service begins by one's hearing about the Lord. Having realized the Lord in terms of form, qualities and powers in truth by bhakti, one joins the Lord in His kingdom by that same bhakti. Bhakti alone is the cause of both realizing the Lord and joining Him. Understanding Kṛṣṇa in truth by pure bhakti, taking that bhakti alone, one joins Him. It is said in Vedānta (4.1.12) that even in liberation bhakti still exists: āprāyaṇāt tatrāpi hi dṛṣṭam: after liberation (āprāyaṇāt) even then (tatrāpi) in liberation, bhakti continues to exist because this is seen from scriptural statements (hi dṛṣṭam).