Forever is not eternity.

for·ev·er

   /fɔrˈɛvər, fər-/ Show Spelled[fawr-ev-er, fer-] Show IPA

–adverb

1.

without ever ending: to last forever.

2.

continually; incessantly; always: He's forever complaining

e·ter·ni·ty

   /ɪˈtɜrnɪti/ Show Spelled[ih-tur-ni-tee] Show IPA

–noun, plural -ties.

1.

infinite time; duration without beginning or end.

2.

eternal existence, especially as contrasted with mortal life: the eternity of god.

3.

Theology . the timeless state into which the soul passes at a person's death.