The Jataka, Vol. III, tr. by H.T. Francis and R.A. Neil, , at sacred-texts.com
"Practise virtue," etc.—The Master told this tale while dwelling in Jetavana, of a deceitful Brother. He said, "Brethren, this man is not deceitful now for the first time": so he told an old-world tale.
Once upon a time when Brahmadatta was king in Benares, the Bodhisatta was born as a bird: when he grew up he lived amidst a retinue of birds on an island in the middle of the sea. Certain merchants of Kāsi got a travelled crow and started on a voyage by sea. In the midst of the sea the ship was wrecked. The crow reached that island and thought, "Here is a great flock of birds, it is good that I use deceit on them and eat their eggs and young": so he descended in their midst and opening his mouth stood with one foot on the ground. "Who are you, master?" they asked. "I am a holy person." "Why do you stand on one foot?" "If I put down the other one,  the earth could not bear me." "Then why do you stand with your mouth open?" "We eat no other food, we only drink the wind;" and with this he called these birds and saying, "I will give you a sermon, you listen," he spoke the first stanza by way of a sermon:
Here and after virtuous people have their happiness complete.
The birds, not knowing that he said this with deceit to eat their eggs, praised him and spoke the second stanza:
He preaches on one leg the holy word.
The birds, believing that wicked one, said, "Sir, you take no other food but feed on wind only: so pray watch our eggs and young," so they went to their feeding-ground. That sinner when they went away ate his bellyful of their eggs and young, and when they came again he stood calmly on one foot with his mouth open. The birds not seeing their children when they came made a great outcry, "Who can be eating them?" but saying, "This crow is a holy person," they do not even suspect him. Then one day the Bodhisatta thought, "There was nothing
wrong here formerly, it only began since this one came, it is good to try him": so making as if he were going to feed with the other birds he turned back and stood in a secret place.  The crow, confident because the birds were gone, rose and went and ate the eggs and young, then coming back stood on one foot with his mouth open. When the birds came, their king assembled them all and said, "I examined to-day the danger to our children, and I saw this wicked crow eating them, we will seize him": so getting the birds together and surrounding the crow he said, "If he flees, let us seize him," and spoke the remaining stanzas:
The things he preaches with his voice At heart a hypocrite, his language charms, Strike him down with beak and pinion,
You spoke with foolish tongue:
"Virtue," he'll say, and "Virtue" aye,
But he eats our eggs and young.
His members never do:
His Virtue is an empty noise,
His righteousness untrue.
A black snake slinking to his hole is he:
He cozens by his outward coat of arms
The country-folk in their simplicity.
Tear him with your claws:
Death to such a dastard minion,
Traitor to our cause.
The things he preaches with his voice
At heart a hypocrite, his language charms,
Strike him down with beak and pinion,
 With these words the leader of the birds himself sprang up and struck the crow in the head with his beak, and the rest struck him with beaks and feet and wings: so he died.
At the end of the lesson, the Master identified the Birth: "At that time the crow was the deceitful Brother, the king of the birds was myself."
170:1 See Morris in Folk-lore Journal, ii. p. 304.