There was a Rishi named Dhaumya who had three disciples in his Gurukul - Upamanyu, Aaruni from Paanchaal country, and Ved. Once a wall broke and water started coming in the farm. If it was not stopped soon it could have spoiled the crop. So Guru Jee asked Aaruni to go there and stop that water from coming in the field.

Aaruni went there and tried his best to stop the water by all means, but he did not succeed in stopping it. Then he found only one way to stop it that he himself should lie down against the wall from where the water was breaking in. So he himself lay down there and he succeeded in stopping it. When he got up from there, the water again broke it up, so he lay down there only.

When Guru Jee didn't see Aaruni for some time, he remembered Aaruni and asked his other disciples where was Aaruni. They said - "Guru Jee, You yourself have sent him to stop the water in the field. Guru Jee remembered it and said - "Yes, I sent him there. But he should have come back by now. Where is he?" Everybody showed his ignorance about him. Since it was evening now, he himself went to that field with his other disciples and called him in a loud voice - "Aaruni, Where are you?" Aaruni also spoke loudly - "Guru Jee, I am here, lying here to stop the water." Guru Jee reached there and saw Aaruni lying there - the water was stopped. Aaruni further spoke - "I could not stop it by any other means so I myself lay down here to stop it. It is only after hearing your voice that I stood up. Now tell me what should I do?"

Guru Jee said - "Since by getting up you have opened the water course, you will now be known as Uddaalak and since you have obeyed me, you will get a good fortune. All Ved and Dharm Shaastra will shine in your heart." Aaruni went away from there.