Old Age
Jarā Sutta  (SN 48:41)

I have heard that on one occasion the Blessed One was staying near Sāvatthī in the Eastern Monastery, the palace of Migāra’s mother. Now on that occasion the Blessed One, on emerging from his seclusion in the evening, sat warming his back in the western sun. Then Ven. Ānanda went to the Blessed One and, on arrival, having bowed down to the Blessed One, massaged the Blessed One’s limbs with his hand and said, “It’s amazing, lord. It’s astounding, how the Blessed One’s complexion is no longer so clear & bright; his limbs are flabby & wrinkled; his back, bent forward; there’s a discernible change in his faculties—the faculty of the eye, the faculty of the ear, the faculty of the nose, the faculty of the tongue, the faculty of the body.”

“That’s the way it is, Ānanda. When young, one is subject to aging; when healthy, subject to illness; when alive, subject to death. The complexion is no longer so clear & bright; the limbs are flabby & wrinkled; the back, bent forward; there’s a discernible change in the faculties—the faculty of the eye, the faculty of the ear, the faculty of the nose, the faculty of the tongue, the faculty of the body.”

That is what the Blessed One said. Having said that, the One Well-Gone, the Teacher, said further:

See also: DN 16; SN 3:25; Thag 1:118; Thig 5:8