Mahāparinibbāna Sutta 3.45.8

3.45.8

Sace tvaṃ, ānanda, tathāgataṃ yāceyyāsi, dveva te vācā tathāgato paṭikkhipeyya, atha tatiyakaṃ adhivāseyya, tasmātihānanda, tuyhevetaṃ dukkaṭaṃ, tuyhevetaṃ aparaddhaṃ.

'On one occasion, Ânanda, I was residing here at Vesâli at the Udena Ketiya. And there too, Ânanda, I spoke to thee, and said: "How pleasant, Ânanda, is Vesâli; how pleasant the Udena Ketiya. Whosoever, Ânanda, has thought out and developed, practised, accumulated, and ascended to the very heights of the four paths to saintship, and so mastered them as to be able to use them as a means of (mental) advancement and as a basis for edification--he, should he desire it, could remain in the same birth for a kalpa, or for that portion of a kalpa which has yet to run." Now the Tathâgata has thought out and thoroughly practised them [in all respects as just now fully described], and might, should he desire it, remain alive for a kalpa, or for that portion of a kalpa which has yet to run.'