Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
When one’s consciousness is uncontaminated by material lusty desires, it becomes calm and peaceful in all activities, for one is situated in eternal blissful life. Once situated on that platform, one does not return to materialistic activities.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Brahma-sukha-sprstam is also described in Bhagavad-gita (18.54):
na socati na kanksati
samah sarvesu bhutesu
mad-bhaktim labhate param
“One who is transcendentally situated at once realizes the Supreme Brahman and becomes fully joyful. He never laments or desires to have anything; he is equally disposed toward every living entity. In this situation, he begins transcendental activities, or devotional service to the Lord.” Generally, once elevated to the transcendental platform of brahma-sukha, transcendental bliss, one never comes down. But if one does not engage in devotional service, there is a chance of his returning to the material platform. Aruhya krcchrena param padam tatah patanty adho ’nadrta-yusmad-anghrayah: one may rise to the platform of brahma-sukha, transcendental bliss, but even from that platform one may fall down to the material platform if he does not engage himself in devotional service.