SB 8.20.13
esa va uttamasloko
na jihasati yad yasah
hatva mainam hared yuddhe
sayita nihato maya
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
If this brahmana really is Lord Visnu, who is worshiped by Vedic hymns, He would never give up His widespread reputation; either He would lie down having been killed by me, or He would kill me in a fight.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Bali Maharaja’s statement that Visnu would lie down having been killed is not the direct meaning, for Visnu cannot be killed by anyone. Lord Visnu can kill everyone, but He cannot be killed. Thus the real meaning of the words “lie down” is that Lord Visnu would reside within the core of Bali Maharaja’s heart. Lord Visnu is defeated by a devotee through devotional service; otherwise, no one can defeat Lord Visnu.