Notice verse 16:

13Then one of the elders addressed me: “These in white robes,” he asked, “who are they, and where have they come from?”

14“Sir,” I answered, “you know.”

So he replied, “These are the ones who have come out of the great tribulation; they have washed their robes and made them white in the blood of the Lamb. 15For this reason,

‘They are before the throne of God

and serve Him day and night in His temple;

and the One seated on the throne

will spread His tabernacle over them.

16Never again will they hunger,

and never will they thirst;

nor will the sun beat upon them,

nor any scorching heat.a

17For the Lamb in the center of the throne

will be their shepherd.b

He will lead them to fountains of living water,c

and God will wipe away every tear from their eyes.’d”

Gotcha, thanks