That he or it (Muhammad SAW or the Quran) may give warning

﴿لِّيُنذِرَ مَن كَانَ حَيّٗا وَيَحِقَّ ٱلۡقَوۡلُ عَلَى ٱلۡكَٰفِرِينَ ﴾
[يسٓ: 70]

That he or it (Muhammad SAW or the Quran) may give warning to him who is living (a healthy minded the believer), and that Word (charge) may be justified against the disbelievers (dead, as they reject the warnings)

﴿لينذر من كان حيا ويحق القول على الكافرين﴾ [يسٓ: 70]

Al Bilal Muhammad Et Al
That it may give advice to any that are alive, and that the charge may be proven against those who reject it

Hamid S Aziz
That it may warn him who would have life, and that the word may prove true against the disbelievers

Mir Aneesuddin
that he who is alive may be warned and the word may be proved true against the disbelievers