The Jataka, Volume I, tr. by Robert Chalmers, , at sacred-texts.com
"How many more?"--This story was told by the Master while at Jetavana, about hankering after the wife of one's mundane life. The incidents of the introductory story will be told in the Indriya-jātaka 1.
The Master spoke thus to the Brother, "It is impossible to keep a guard over a woman; no guard can keep a woman in the right path. You yourself found in former days that all your safeguards were unavailing; and how can you now expect to have more success?"
And so saying, he told this story of the past.
Once on a time when Brahmadatta was reigning in Benares, the Bodhisatta was born a parrot. A certain brahmin in the Kāsi country was as a father to him and to his younger brother, treating them like his own children. Poṭṭhapāda was the Bodhisatta's name, and Rādha his brother's.
Nov the brahmin had a bold bad wife. And as he was leaving home on business, he said to the two brothers, "If your mother, my wife, is minded to be naughty, stop her." "We will, papa," said the Bodhisatta, "if we can;  but if we can't, we will hold our peace."
Having thus entrusted his wife to the parrots' charge, the brahmin set out on his business. Every day thenceforth his wife misconducted herself; there was no end to the stream of her lovers in and out of the house. Moved by the sight, Rādha said to the Bodhisatta, "Brother, the parting injunction of our father was to stop any misconduct on his wife's part, and now she does nothing but misconduct herself. Let us stop her."
[paragraph continues] "Brother," said the Bodhisatta, "your words are the words of folly. You might carry a woman about in your arms and yet she would not be safe. So do not essay the impossible." And so saying he uttered this stanza:--
And for the reasons thus given, the Bodhisatta did not allow his brother to speak to the brahmin's wife, who continued to gad about to her heart's content during her husband's absence. On his return, the brahmin asked Poṭṭhapāda about his wife's conduct, and the Bodhisatta faithfully related all that had taken place.
"Why, father," he said, "should you have anything more to do with so wicked a woman?" And he added these words,--"My father, now that I have reported my mother's wickedness, we can dwell here no longer." So saying, he bowed at the brahmin's feet and flew away with Rādha to the forest.
His lesson ended, the Master taught the Four Truths, at the close whereof the Brother who hankered after the wife of his mundane life was established in the fruition of the first Path.
"This husband and wife," said the Master, "were the brahmin and his wife of those days, Ānanda was Rādha, and I myself Poṭṭhapāda."
309:1 No. 423.