The Jataka, Volume I, tr. by Robert Chalmers, , at sacred-texts.com
"’Tis not the cold."--This story was told by the Master while at Jetavana, about being seduced by the wife of one's mundane life before joining the Brotherhood. Said the Master on this occasion, "Is it true, as I hear, Brother, that you are passion-tost?"
"Yes, Blessed One."
"Because of whom?"
"My former wife, sir, is sweet to touch; I cannot give her up! "Then said the Master, "Brother, this woman is hurtful to you. It was through her that in bygone times too you were meeting your end, when you were saved by me." And so saying, he told this story of the past.
Once on a time when Brahmadatta was reigning in Benares, the Bodhisatta became his family-priest.
In those days some fishermen had cast their net into the river. And a great big fish came along amorously toying with his wife. She, scenting the net as she swam ahead of him, made a circuit round it and escaped. But her amorous spouse, blinded by passion, sailed right into the meshes of the net. As soon as the fishermen felt him in their net, they hauled it in and took the fish out; they did not kill him at once, but flung him alive on the sands.  "We'll cook him in the embers for our meal," said they; and accordingly they set to work to light a fire and whittle a spit to roast him on. The fish lamented, saying to himself, "It's not the torture of the embers or the anguish of the spit or any other pain that grieves me; but only the distressing thought that my wife should be unhappy in the belief that I have gone off with another." And he repeated this stanza:--
Just then the priest came to the riverside with his attendant slaves to bathe. Now he understood the language of all animals. Therefore, when he heard the fish's lamentation, he thought to himself, "This fish is lamenting the lament of passion. If he should die in this unhealthy state of mind, he cannot escape rebirth in hell. I will save him." So he went to the fishermen and said, "My men, don't you supply us with a fish every day for our curry?" "What do you say, sir?" said the fishermen; "pray take away with you any fish you may take a fancy to." "We don't need any but this one; only give us this one." "He's yours, sir."
Taking the fish in his two hands, the Bodhisatta seated himself on the bank and said, "Friend fish, if I had not seen you to-day, you would have met your death. Cease for the future to be the slave of passion." And with this exhortation he threw the fish into the water, and went into the city.
 His lesson ended, the Master preached the Truths, at the close whereof the passion-tost Brother won the First Path. Also, the Master shewed the connexion and identified the Birth by saying, "The former wife was the female fish of those days, the passion-tost Brother was the male fish, and I myself the family-priest."
[Note. Compare Jātakas Nos. 216 and 297.]