evam krsna-mater brahman
kalah pradurabhut kale
tadit saudamani yatha
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
And so, O Brahmana Vyasadeva, in due course of time I, who was fully absorbed in thinking of Krsna and who therefore had no attachments, being completely freed from all material taints, met with death, as lightning and illumination occur simultaneously.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila PrabhupadaP:
To be fully absorbed in the thought of Krsna means clearance of material dirts or hankerings. As a very rich man has no hankerings for small petty things, so also a devotee of Lord Krsna, who is guaranteed to pass on to the kingdom of God, where life is eternal, fully cognizant and blissful, naturally has no hankerings for petty material things, which are like dolls or shadows of the reality and are without permanent value. That is the sign of spiritually enriched persons. And in due course of time, when a pure devotee is completely prepared, all of a sudden the change of body occurs which is commonly called death. And for the pure devotee such a change takes place exactly like lightning, and illumination follows simultaneously. That is to say a devotee simultaneously changes his material body and develops a spiritual body by the will of the Supreme. Even before death, a pure devotee has no material affection, due to his body’s being spiritualized like a red-hot iron in contact with fire.