The Jataka, Vol. III, tr. by H.T. Francis and R.A. Neil, , at sacred-texts.com
"For one who is asking," etc.—This was a story told by the Master, while living at Jetavana, as to how the Elder Sāriputta procured dainty fare for some sick Brothers under medical treatment. The story goes that certain of the Brethren at that time at Jetavana, after taking oil as a purgative, wished for some dainty food. Those who ministered to them in their sickness went into Sāvatthi to fetch some dainties, but after going their round for alms in a street in the Cooks' quarters, had to come back without getting what they wanted. Later on in the day the Elder was going into the town for alms and meeting these Brethren asked them why they had returned so soon. They told him
what had happened. "Come then with me," said the Elder,  and took them to the very same street. And the people there gave him a full measure of dainty fare. The attendants brought the food to the sick Brethren, and they partook of it. So one day a discussion was started in the Hall of Truth how that when some servants were leaving a town, without being able to get dainty fare for their sick masters, the Elder took them with him on his round for alms in a street in the Cooks' quarters, and sent them home with abundant dainties. The Master came up and inquired the nature of their discussion, and on being told what it was he said, "Not now only, Brethren, did Sāriputta alone obtain food. Formerly also wise men who had a soft voice and knew how to speak pleasantly obtained the same." And then he told a tale of the olden time.
Once upon a time when Brahmadatta reigned in Benares, the Bodhisatta was born as the son of a wealthy merchant.
Now one day a certain deer-stalker had taken venison, and filling his cart with the meat, returned to the city with the intention of selling it. At this time four sons of rich merchants who were living in Benares sallied out of the city, and meeting at some cross roads they sat down and conversed with one another about whatever they had seen or heard. One of these youths on seeing the cart full of meat proposed to go and get a piece of venison from the hunter. The others bade him go and try. So he went up to the hunter, and said, "Hi, Sirrah, give me a piece of meat." The hunter replied, "A man who begs somewhat from another ought to speak with a gentle voice: you shall receive a piece of meat appropriate to your manner of speech." Then he uttered the first stanza:—
For one who is asking a favour, my friend, thy language is coarse in its tone,
Such language deserves coarse fare in return, so I offer thee mere skin and bone.
Then one of his companions asked him what language he had used in begging for a piece of meat. "I said, Hi, Sirrah!" he replied. "I too," said the other, "will beg of him."  Then he went to the hunter and said, "O elder brother, give me a piece of venison." The hunter answered, "You shall receive such a piece as the words you have spoken deserve," and he repeated the second stanza:—
The name of a brother a strong link is found, to join those akin to each other,
As thy kind words suggest the gift I should make, so a joint I present to my brother.
And with these words he took up and threw him a joint of venison. Then a third youth inquired with what words the last had begged for the meat. "I addressed him as brother," he replied. "Then I too will beg of him," he said. So he went to the hunter and cried, "Dear father, give me a piece of venison." The hunter replied, "You shall receive a
piece suitable to the words you have spoken," and he repeated the third stanza:—
As a parent's fond heart to pity is moved, the cry of "Dear father" to hear,
So I too respond to thy loving appeal, and give thee the heart of the deer.
And with these words he picked up and gave him a savoury piece of meat, heart and all. Then the fourth of the youths asked the third youth, with what words he had asked for the venison. "Oh I called him "Dear father," he answered. "Then I too will beg a piece," said the other, and he went to the hunter and said, "My friend, give me a piece of meat." Said the hunter, "According to the words you have spoken, shall you receive." And he repeated the fourth stanza:—
A world without friends, I venture to think, a wilderness surely must be,
In that title of friend all that's dear is implied, so I give all the deer unto thee.
Moreover he said, "Come, friend, I will convey all this cartful of meat to your house."  So this merchant's son had the cart driven to his house, and he went and unloaded the meat. And he treated the hunter with great hospitality and respect, and sending for his wife and son he took him away from his cruel occupation, and settled him on his own estate. And they became inseparable friends, and all their life long lived amicably together.
The Master, having ended his lesson, identified the Birth: "At that time Sāriputta was the Hunter, and I myself was the Merchant's Son who had all the venison given to him."
32:1 See R. Morris, Folklore Journal, iii. 242.