oracle:

any person or thing believed to indicate future action with infallible authority

oracle:

any person or thing believed to indicate future action with infallible authority

(Noun)

Example Sentences:

Ramayana:  On seeing what looked like the beheaded body of Rama, Sita lamented, “Alas! The oracle of the astrologers at my marriage that I would never become a widow has turned out to be false.”

Mahabharata:  As Duryodhana watched the ragged remains of his once vast army, he realized the truth of the oracle of all the sages who had warned him about Krishna’s divinity and the Pandavas’ might thereof. 

Bhagavad-gita:  The concluding verse of the Gita is an oracle by Sanjaya who has understood the divinity of Krishna and the unstoppability of his divine will.