Rahu had been drinking nectar through his mouth, & before the nectar entered his body, his head was cut off. Thus his head remained alive whereas the body died. This wonderful act performed by the God was meant to show that nectar is miraculous ambrosia

Expressions researched:
"Rāhu had been drinking nectar through his mouth, and before the nectar entered his body, his head was cut off. Thus Rāhu's head remained alive whereas the body died. This wonderful act performed by the Lord was meant to show that nectar is miraculous ambrosia"

Srimad-Bhagavatam

SB Canto 8

When the Personality of Godhead, Mohinī-mūrti, severed Rāhu's head from his body, the head remained alive although the body died. Rāhu had been drinking nectar through his mouth, and before the nectar entered his body, his head was cut off. Thus Rāhu's head remained alive whereas the body died. This wonderful act performed by the Lord was meant to show that nectar is miraculous ambrosia.

SB 8.9.25, Translation and Purport

The Supreme Personality of Godhead, Hari, using His disc, which was sharp like a razor, at once cut off Rāhu's head. When Rāhu's head was severed from his body, the body, being untouched by the nectar, could not survive.

When the Personality of Godhead, Mohinī-mūrti, severed Rāhu's head from his body, the head remained alive although the body died. Rāhu had been drinking nectar through his mouth, and before the nectar entered his body, his head was cut off. Thus Rāhu's head remained alive whereas the body died. This wonderful act performed by the Lord was meant to show that nectar is miraculous ambrosia.