Why we do what we do: The Heart Sūtra or Sherab Nyingpo (ཤེས་རབ་སྙིང་པོ་) is perhaps the most popular Buddhist sūtra and certainly the sūtra most widely used and chanted in Bhutan. Its full title in Sanskrit is Bhagavatīprajñāpāramitāhṛdaya and in Choekey བཅོམ་ལྡན་འདས་མ་ཤེས་རབ་ཀྱི་ཕ་རོལ་ཏུ་ཕྱིན་པའི་སྙིང་པོ་ which translates as The Heart of the Blessed Perfection of Wisdom. The followers of Mahāyāna Buddhism consider it as a sacred literature which falls within the category of the words of the Buddha. Thus, it is placed within the Perfection of Wisdom (ཤེར་ཕྱྱིན་) section of the kangyur (བཀའ་འགྱུར་) canon.
There is no consensus among scholars on the origin of the Heart Sūtra. While the adherents of Mahāyāna Buddhism, particularly those following the Perfection of Wisdom sūtras, believe that the Heart Sūtra has its origin at the time of the Buddha as it is described in the beginning of the sūtra, most academic scholars argue that the Mahāyāna sutras were composed much later around the beginning of the Christian era during the rise of the Mahāyāna school. Some researchers even argue that the Heart Sūtra was developed in China based on the larger Perfection of Wisdom sūtras. Among the many Perfection of Wisdom sūtras which are available to us, the Heart Sūtra and the Diamond Sūtra are considered to be last compositions as the summary and essence of earlier elaborate ones.
According to the sūtra itself, the Heart Sūtra was taught by the Buddha while he was on Vulture Peak, Rajagṛha with his monastic and Bodhisattva followers. The Buddha entered a meditation state called Profound Illumination and through his power made Śāriputra query Avalokiteśvara about how a person engages in the practice of Perfection of Wisdom. The main sūtra is the response Avalokiteśvara gives Śāriputra instructing how a son or daughter of a noble family should view as empty (སྟོང་པར་རྣམ་པར་བལྟ་བར་བྱ་) everything including form, sensation, feelings, volitions, consciousness, the six sense faculties, the six sense fields, the six consciousnesses, the twelve links of dependent origination and the four nobles. He puts this in the formulaic phrase: form is emptiness,
emptiness is form, emptiness is no other than form and form is no other than emptiness.
Avalokiteśvara goes on to claim that there is nothing to gain or not gain and the Bodhisattva, with no expectation of gain, and hence with no hindrances or fear and by relying on and abiding in the Perfection of Wisdom, will transcend what is wrong and realize the state of nirvāṇa. The main body of the sūtra ends with the mantra or dharaṇi spell of Perfection of Wisdom: Om gate gate pāra gate pārasaṃgate Bodhi svaha (Oṃ gone, gone, gone beyond, gone fully beyond, to Awakening! All hail!). The sūtra ends with the Buddha rising up from his meditation absorption and praising Avalokiteśvara for his exposition and finally the gathering of followers praise and rejoice in the words of the Buddha, as is normally the case with the conclusion of sūtras.
In Bhutan, the Heart Sūtra is widely chanted as a regular prayer and forms an essential part of khathun prayers. It is commonly used during difficult times in order to overcome illnesses and misfortunes. After chanting the full sūtra, Bhutanese often recite the mantra numerous times and then chant a say the prayers which call on the power of the Three Jewels and the Perfection of Wisdom to dispel all negative and harmful forces including diseases, evil spirits, obstacles, etc. Thus, the Heart Sūtra is more commonly used as a prayer to annihilate obstacles and difficulties rather than as a reminder to view life and its problems as empty and illusory. It is used popularly in a ritual called Shernying Duedog (ཤེར་སྙིང་བདུད་བཟློག་), a ritual to avert evil forces using the power of the Heart Sūtra.
Although it is often sadly used for reinforcing one’s attachment to oneself and things, the core and ultimate message of the Heart Sūtra is to view things as empty and unreal and overcome the human sense of attachment to existence. It is through the perfection of wisdom, which sees that there is nothing real to gain or not gain, that we can drop our obsession with persons, properties and ideas, and be truly liberated from the clutches of attachment and apprehension.