11 Heb “and he says.” Apparently a second “voice” responds to the command of the first “voice.”
12 The words “the first voice responds” are supplied in the translation for clarification. The first voice tells the second one what to declare.
13 Heb “all flesh is grass.” The point of the metaphor is explained in v. 7.
14 Heb “and all his loyalty.” The antecedent of the third masculine suffix is בָּשָׂר (basar, “flesh”), which refers collectively to mankind. The , apparently understanding the antecedent as “grass,” reads “glory,” but חֶסֶד (khesed) rarely, if ever, has this nuance. The normal meaning of חֶסֶד (“faithfulness, loyalty, devotion”) fits very well in the argument. Human beings and their faithfulness (verbal expressions of faithfulness are specifically in view; cf. “constancy”) are short-lived and unreliable, in stark contrast to the decrees and promises of the eternal God.

In other versions

A voice says, “Cry!”

And I said, “What shall I cry?”

All flesh is grass,

and all its beauty is like the flower of the field.

A voice says, “Cry out.”

And I said, “What shall I cry?”

“All people are like grass,

and all their faithfulness is like the flowers of the field.

A voice was saying, “Cry out!”

Another said, “What should I cry out?”

“All humanity is grass,

and all its goodness is like the flower of the field.

A voice said, “Shout!”

I asked, “What should I shout?”

“Shout that people are like the grass.

Their beauty fades as quickly

as the flowers in a field.

A voice is saying, “Call!”

And he said, “What shall I call?”

All humankind are grass,

and all his loyalty is like the flowers of the field.

The voice said, Cry.

And he said, What shall I cry?

All flesh is grass,

And all the goodliness thereof is as the flower of the field:

Public Domain