46 Heb “and there will not be from there again a nursing infant of days,” i.e., one that lives just a few days.
47 Heb “or an old [man] who does not fill out his days.”
48 Heb “for the child as a son of one hundred years will die.” The point seems to be that those who die at the age of a hundred will be considered children, for the average life span will be much longer than that. The category “child” will be redefined in light of the expanded life spans that will characterize this new era.
49 Heb “the one who misses.” חָטָא (khata’) is used here in its basic sense of “miss the mark.” See חטא. Another option is to translate, “and the sinner who reaches the age of a hundred will be cursed.”

In other versions

No more shall there be in it

an infant who lives but a few days,

or an old man who does not fill out his days,

for the young man shall die a hundred years old,

and the sinner a hundred years old shall be accursed.

“Never again will there be in it

an infant who lives but a few days,

or an old man who does not live out his years;

the one who dies at a hundred

will be thought a mere child;

the one who fails to reach a hundred

will be considered accursed.

In her, a nursing infant will no longer live

only a few days,

or an old man not live out his days.

Indeed, the one who dies at a hundred years old will be mourned as a young man,

and the one who misses a hundred years will be considered cursed.

“No longer will babies die when only a few days old.

No longer will adults die before they have lived a full life.

No longer will people be considered old at one hundred!

Only the cursed will die that young!

There will no longer be a nursing infant who lives only a few days,

or an old man who does not fill his days,

for the boy will die a hundred years old,

and the one who fails to reach a hundred years will be considered accursed.

There shall be no more thence an infant of days,

Nor an old man that hath not filled his days:

For the child shall die an hundred years old;

But the sinner being an hundred years old shall be accursed.

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