[739] Now at that time there was a festival in Sāvatthī. People, adorned and dressed up, went to the pleasure garden. Visākhā, Migāra's mother, also, adorned and dressed up, left the village thinking, "I shall go to the pleasure garden." Then she thought, "What shall I do by going to the pleasure garden? Suppose I were to pay my respects to the Blessed One." She took off her ornaments, bound them into a bundle with her upper robe, and gave it to her slave-woman, saying, "Here, girl, take this bundle." Then Visākhā, Migāra's mother, approached the Blessed One; having approached and paid homage to the Blessed One, she sat down to one side. As Visākhā, Migāra's mother, sat to one side, the Blessed One instructed, inspired, roused, and gladdened her with a talk on the Dhamma. Then Visākhā, Migāra's mother, having been instructed, inspired, roused, and gladdened by the Blessed One with a talk on the Dhamma, rose from her seat, paid homage to the Blessed One, circumambulated him keeping her right side towards him, and departed. Then that slave-woman went away, having forgotten that bundle. Bhikkhus saw it and reported the matter to the Blessed One. [He said:] "Well then, bhikkhus, pick it up and put it away."
Then the Blessed One, on account of that occasion, in that connection, having given a talk on the Dhamma, addressed the bhikkhus: "Bhikkhus, I allow you, within a monastery (ajjhārāma), to pick up, or have picked up, a valuable (ratana) or what is regarded as a valuable, and to put it away, [thinking,] 'Whoever it belongs to will take it away.' And thus, bhikkhus, you should recite this training rule (sikkhāpada): Whatever bhikkhu should pick up, or have picked up, a valuable or what is regarded as a valuable, except within a monastery, there is an offense entailing confession (pācittiya)."
And thus this training rule was laid down by the Blessed One for the bhikkhus.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.