Because he says in another Psalm, You will not let your Holy One see destruction.
For you will not let my soul be prisoned in the underworld; you will not let your loved one see the place of death.
So that he might have eternal life, and never see the underworld.
What man now living will not see death? will he be able to keep back his soul from the underworld? Selah.
And he had knowledge, through the Holy Spirit, that he would not see death till he had seen the Lord's Christ.
He who has faith in the Son has eternal life; but he who has not faith in the Son will not see life; God's wrath is resting on him.
Truly I say to you, If a man keeps my word he will never see death.
By faith Enoch was taken up to heaven so that he did not see death; he was seen no longer, for God took him away: for before he was taken, witness had been given that he was well-pleasing to God: