Old Hope (Q."Estel Enwina") referred to an ancient teaching among the Edain. According to their lore their ancestors had traded down to them the hope that one day the voice would enter it's creation incarnated as Eruhin and would heal all men from mortality and the dark King's marring of Arda from it's beginning to the end.
In a modified form the Old Hope became one of the central teachings of the Eruist religion among the Dúnedain. A very similar tale had prevailed among Gwathuirim such as Agaldor.
See:
- Second Music of the Ainur