'Forever' in the Bible

I am the living bread that came down from heaven. If anyone eats of this bread he will live forever. The bread that I will give for the life of the world is My flesh.”

This is the bread that came down from heaven; it is not like the manna your fathers ate—and they died. The one who eats this bread will live forever.”

A slave does not remain in the household forever, but a son does remain forever.

Then the crowd replied to Him, “We have heard from the scripture that the Messiah will remain forever. So how can You say, ‘The Son of Man must be lifted up’? Who is this Son of Man?”

And I will ask the Father, and He will give you another Counselor to be with you forever.