sempiternity

/ˌsɛmpɪˈtɜrnɪti/
noun
  1. The state or quality of lasting forever; endless duration; eternity.
    • For the ancient Greeks, the gods enjoyed a sempiternity that humans could only dream of.
    • The poet wrote of the soul's journey into sempiternity beyond the mortal world.
    • Philosophers have long debated the nature of sempiternity and whether time has a beginning.