The Only Duty of a Disciple

A sage by the name of Ayoddhaumya had his hermitage in the forest. Out of all the students Aruni was the most sincere disciple. Sage Dhaumya himself was very hard working and taught his students the same. All of his students were very obedient and they used to finish their tasks in right earnest.
One day it was raining heavily. Sage Dhaumya ordered Aruni to build a bund in the fields so the swift water current did not erode the fields, otherwise the yield would be adversely impacted. Aruni obeyed the command of his teacher and went to the fields. Since it was raining very heavily, the field was filled up with water. But at one end of the field, the swift current washed a portion of the boundary away. The current of the water was gushing out very fast from that place. Aruni tried to stop the water from flowing out by putting some soil in that place by the help of a spade.
But the swift current washed it away. He tried many times but all his efforts went in vain. Now, he started worrying because he was not able to obey the command of his teacher. Suddenly, an idea came to his mind and he kept aside the spade and fay down at the place from where the water was gushing out. After sometime, it stopped raining but he could not get up because the water would have flown outside the field. So, he kept lying in the same position.
Next morning, when Sage Dhaumya did not see Aruni at his service as usual, called all his students to enquire about Aruni's whereabouts. The students replied that: "Guru ji, you had sent him to build a bund in the field." Sage Dhaumya became worried and he along with the other students went in search of Aruni with a lantern in his hand. But they could not find Aruni anywhere.
Sage Dhaumya called him out several times: " Aruni, where are you, we are searching for you." Aruni heard his teacher's voice and replied in that same position: " Guru Ji, here I am". Sage Dhaumya followed the direction from which Aruni's voice came. When he found Aruni lying in place of a bund, his heart was overcome with love. He called Aruni and embraced him. He blessed Aruni by saying: " Son Aruni! I am very pleased by your devotion; you will acquire every kind of knowledge even without studying. You will become famous in this world and will become the supreme devotee of God. From today, onwards you will be known as 'Uddalak'. The same Aruni became famous as sage 'Uddalak'.