Can somebody please explain the meaning of "to-be" here:
Yet we should not be disappointed at the sight of an empty seat, for the power of the sacred place still resonates and can be felt by anyone who stands in the presence of the spot where the Buddha-to-be sat and was sheltered by the sacred tree on the day of his awakening.
As I understand, it's about an event in the future but why then did the author use past simple after that?