The Life of the Buddha: Conversion of Pukkusa.
Immediately after this there passed by a young man, by name Pukkusa, a disciple of Alara Kalama. And he related to the Buddha how upon a certain occasion this Alara Kalama had been sitting beside the road, and was so absorbed in meditation that five hundred carts passed him by, so nearly that even his robe was sprinkled with the dust; and a certain man was so much impressed by this profound abstraction that he became Alara's disciple. Upon hearing this story the Buddha replied by relating an occasion of even greater abstraction, on his own part, when, as he was walking to and fro upon a certain threshing-floor at Atuma, the rain fell and lightning flashed, and two peasants and four men were killed by a thunderbolt and yet though conscious and awake, he neither saw nor heard the storm; and upon that occasion in like manner a certain man was so much impressed by the Master's abstraction that he became a disciple.
Upon hearing this relation, Pukkusa's faith in Alara Kalama faded away, and he resorted to the Exlted One, and to the Law and to the Brotherhood as his refuge, and requested the Exalted One to accept him as a lay disciple. And he sent for two robes of cloth of gold and presented them to the Master, and so went his way. But when Ananda folded the robes and the Master wore them, the golden cloth seemed to have lost its brightness and this was because whenever One-who-has-thus-attained attains to Perfect Englightenment, as also on the day when he passes away, the colour of his skin becomes exceeding bright. "And now," said the Master, "the utter passing away of Him-who-has-thus-attained, will take place at the third watch of this night in the Sala-grove of the Mallians. Come, Ananda, let us go on to the river Kakuttha." "Even so, lord!" said the venerable Ananda.
The Exalted One went down into the water of the river Kakuttha, and bathed and drank; and then, taking his seat upon the bank, he spoke with Ananda concerning Cunda the smith, that none should impute the least blame to him because the Master died after receiving the last meal at his hands. On the contrary, he said, there are two offering sof food which are supremely precious that which is given immediately before One-who-has-thus-come attains to Perfect Insight, and the other before his utter passing away; and "there had been laid up to Cunda the smith a kamma redounding to length of life, good birth, good fortune and good fame, and to the inheritance of heaven and of sovereign power; and therefore let not Cunda the smith feel any remorse."