[131] When this was said, the Blessed One said this to Māra the Evil One: "Be untroubled, Evil One. Before long the final Nibbāna (parinibbāna) of the Tathāgata will take place: when three months have passed from now, the Tathāgata will attain final Nibbāna."
Then the Blessed One, at the Pāvāla Shrine (Pāvālacetiya), mindful and clearly comprehending, relinquished the life-formation (āyusaṅkhāra). And when the life-formation had been relinquished by the Blessed One, there was a great earthquake, terrifying and hair-raising, and the drums of the devas burst forth.
Then the Blessed One, understanding the significance of this, on that occasion uttered this inspired utterance (udāna):
"Becoming (sambhava), both the measurable and the immeasurable —
the sage (muni) relinquished the formation of existence (bhavasaṅkhāra);
rejoicing within, concentrated,
he broke the arising of self like a coat of mail."
The First Sutta.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.