The Yogasutra of Patanjali talks about a two-fold approach to achieve chitta vritti: Abhayasa and Vairagya
अभ्यासवैराग्याभ्यां तन्निरोधः॥१२॥ Abhyāsavairāgyābhyāṁ tannirodhaḥ||1.12||
Bhagavan Sri Krishna too talks about this in the Bhagavad Gita. For Arjuna’s remark that controlling the mind seems more difficult that controlling the wind, Shri Krishna acknowledges and says that the mind can be controlled through abhyasa and vairagya.
चञ्चलं हि मन: कृष्ण प्रमाथि बलवद्दृढम् | तस्याहं निग्रहं मन्ये वायोरिव सुदुष्करम् || 34|| chañchalaṁ hi manaḥ kṛiṣhṇa pramāthi balavad dṛiḍham tasyāhaṁ nigrahaṁ manye vāyor iva su-duṣhkaram The mind is very restless, turbulent, strong and obstinate, O Krishna. It appears to me that it is more difficult to control than the wind.
असंशयं महाबाहो मनो दुर्निग्रहं चलम् | अभ्यासेन तु कौन्तेय वैराग्येण च गृह्यते || 35|| asanśhayaṁ mahā-bāho mano durnigrahaṁ chalam abhyāsena tu kaunteya vairāgyeṇa cha gṛihyate Lord Krishna said: O mighty-armed son of Kunti, what you say is correct; the mind is indeed very difficult to restrain. But by practice and detachment, it can be controlled.
Vairagya can be defined as detachment where we are no longer attached to the fruits of our action. Though it seems like a very difficult thing, we develop this over a period of time and with happy and bitter life experiences.
Patanjali Maharishi defines Vairagya as
दृष्टानुश्रविकविषयवितृष्णस्य वशीकारसञ्ज्ञा वैराग्यम्॥१५॥ Dṛṣṭānuśravikaviṣayavitṛṣṇasya vaśīkārasañjñā vairāgyam||1.15||
Vairāgya or Renunciation (vairāgyam) is known (sañjñā) as the act of subjugating (vaśīkāra) the desire (vitṛṣṇasya) for objects (viṣaya) seen (dṛṣṭa) or repeatedly heard from the scriptures (ānuśravika)||1.15||
A similar definition can be noticed in the Tattva Bodha
इहस्वर्गभोगेषु इच्छाराहित्यम् ।
The absence of desire for the enjoyment (of the fruits of one’s actions) in this world, as also in the other world.
This can be illustrated by the story of Rishi Mudgala and his great Tapasya. The story appears in the Vrihi Drounika Parva of the Mahabharata. Yudhishtira asks Vyasa Maharishi “Which is great? Dana or Tapasya?” Vyasa Maharishi says that nothing more is difficult than giving what has been earned with great effort. Hence Dana is great. He goes on to narrate the story of Rishi Mudgala. Rishi Mudgala lived in Kurukshetra and lived on grains that he gathered. He adhered to the Unchavritti tradition of partaking grains that are collected from those that are leftover in the fields or markets. He served the guests and partook of what was left. For a fortnight his family would eat and the remaining days he would collect a drona of vrihi. He enjoyed great reputation for this dana and several brahmanas used to come and eat there.
Once Durvasa Maharishi, in the form of a dishevelled lunatic, approached Mudgala Maharishi and expressed his desire to have food. Mudgala Maharishi offered his respects to Durvasa Maharishi and served him all the food he had. Durvasa had a hearty meal and he left. For the next tithi too he appreared and finished all the food.Inspite of having no grain to consume, Mudgala Maharishi did not display any anger or jealousy, disrespect or agitation. Durvasa Maharishi was extremely happy and he said “Control of the senses, fortitude, generosity, self-control, serenity, compassion, truthfulness and dharma are all established in you. You will go to heaven in your own body”. Messengers from heaven came readily to pick up Mudgala maharishi. Mudgala Maharishi asked the messengers “Can you describe heaven? What is nature of those that are in heaven? What austerities are followed?”. The messengers described heaven in glowing terms, leaving no detail. They even described the worlds beyond. Listening to this Mudgala Maharishi did not develop any interest to go to heaven. He told the messengers that he has no desire to go to heaven. He returned to his life of collecting grains and engaged in meditation. He attained Moksha.
The story of this great Rishi Mudgala who had no desire in the world or elsewhere illustrates Vairagya as described in our shastras.