The holy name of the Lord is as powerful as the Lord Himself. Therefore, simply by chanting and hearing the holy name of the Lord, many men can be fully protected from fierce death without difficulty. Thus a devotee is saved.

By the grace of the Lord, if a devotee, at the time of death, can simply chant His holy name — Hare Krsna, Hare Krsna, Krsna Krsna, Hare Hare / Hare Rama, Hare Rama, Rama Rama, Hare Hare — simply by chanting this maha-mantra, he immediately surpasses the great ocean of the material sky and enters the spiritual sky. He never has to come back for repetition of birth and death. Simply by chanting the holy name of the Lord, one can surpass the ocean of death.

From Srila Prabhupada’s translation & purport to SB 4.10.30