From Srimadh Bagavatha Mahapuranam
Maharaja Ambarisha was a great devotee of Narayana and though he was a great king possessing of immense wealth and fame he considered everything as worthless and transitory due to his devotion to the Lord. He was engaged in worship of the Lord and service to the holy men and devotees and turned away from sensual pleasures. Pleased with his bhakthi the Lord gave him the Sudarsana chakra to protect him from evil forces.
He engaged all his senses in devotional service, in various engagements related to the Lord. This is the way to increase attachment for the Lord and be completely free from all material desires.
He observed Ekadasi and dvadasi vrata for one year with his wife. In the month of karthika when the vrata was about to finish he fasted for three days after bathing in the river yamuna and worshipped Lord Hari in Madhuvana doing mahaabhisheka, with fragrant oil, panchaamrtham, ghee, milk,curd, honey, sugarcane juice, fruit juice, coconut water, sandal paste and holy water.
King first sumptuously fed all the brahmanas, and when they were fully satisfied, he was about to observe the end of Ekadasi, with their permission, by breaking the fast. Exactly at that time, Durvasa Muni, appeared on the scene as an uninvited guest. King Ambarisha offered him a seat and requested the great sage to eat.
Durvasa Muni gladly accepted the request of Maharaja Ambarisha, but to perform the regulative ritualistic ceremonies he went to the River Yamuna.
In the meantime, only a muhurta of the Dvadasi day was left on which to break the fast. After consulting with the brahmanas, the King reached this decision, for according to brahminical opinion, drinking water may be accepted as eating and also as not eating.
After executing the ritualistic ceremonies to be performed at noon, Durvasa returned from the bank of the Yamuna. The King received him well, offering all respects, but Durvasa Muni, by his mystic power, could understand that King Ambarisha had drunk water without his permission.
Still hungry, Durvasa Muni, his body trembling, his face curved and his eyebrows crooked in a frown, angrily spoke as follows to King Ambarisha, who stood before him with folded hands.
“Maharaja Ambarisha, you have invited me to eat as a guest, but instead of feeding me, you yourself have eaten first. Because of your misbehavior, I shall show you something to punish you”
As Durvasa Muni said this, his face became red with anger. Uprooting a bunch of hair from his head, he created a demon resembling the blazing fire of devastation to punish Maharaja Ambarisha.
Taking a trident in his hand and making the surface of the earth tremble with his footsteps, that blazing creature came before Maharaja Ambarisha. But the King, upon seeing him, was not at all disturbed and did not move even slightly from his position.
By the previous order of the Supreme Personality of Godhead, His disc, the Sudarsana chakra, immediately burnt to ashes the created demon to protect the Lord’s devotee.
Upon seeing that his own attempt had failed and that the Sudarsana cakra was moving toward him, Durvasa Muni became very frightened and began to run in all directions to save his life.
Durvasa Muni, the great mystic, scorched by the heat of the Sudarsana cakra, fell at the lotus feet of Narayana. His body trembling, he spoke as follows: O infallible, unlimited Lord, protector of the entire universe, You are the only desirable objective for all devotees. I am a great offender, my Lord. Please give me protection.
The Supreme Personality of Godhead said to the brahmana: I am completely under the control of My devotees. Indeed, I am not at all independent. Because My devotees are completely devoid of material desires, I sit only within the cores of their hearts. What to speak of My devotee, even those who are devotees of My devotee are very dear to Me.
O best of the brahmanas, you should therefore go immediately to King Ambarisha, the son of Maharaja Nabhaga. I wish you all good fortune. If you can satisfy Maharaja Ambarisha, then there will be peace for you.
The sage went to Amabrisha and fell at his feet, who was upset that a great sage had thus fallen at his feet and prayed to Sudarsana by 9 slokas. Then he said that if it were true that his clan was pious doing dhana dharma yaga etc. and worshipped Brahmins and if Lord Hari was pleased with them then this brahmin should be free from fear. Then Sudarasana Chakra which was tormenting the sage from all sides was pacified. Durvasa praised Ambarisha and went away after accepting the food from him.
With the above story we all come to know the greatness of the bakthi and bagavathas.