SIDH GOSṬl, i.e, discourse or dialogue with the Siddhas or mystics adept in haṭha yoga and possessing supernatural powers, is the title of one of Gurū Nānak’s longer compositions recorded in the Gurū Granth Sāhib. A goshṭī (gosṭhī) seeks to expound the respective doctrines of scholars or saints participating in it, revealing in the process their dialectical prowess and learning. In the Sidh Gosṭī all the questions are raised by the Siddhas and all the answers come from Gurū Nānak. It brings out strikingly the crux of his teaching, especially in relation to the Siddhas' philosophy and way of life. The text itself does not provide any clue as to the time and place of its composition, though it is generally placed in the last years of Gurū Nānak’s life when he had finally settled down at Kartārpur after completing his major preaching odysseys. And, the composition might not be the record of any of the goshṭis that are said to have occurred at Gorakh Haṭrī, Gorakh Matā, also known as Nānak Matā, Sumer Parbat and Achal Baṭālā, but a recollection in tranquillity of the major points from discourses between Gurū Nānak and the Siddhas at any of these or other places. The Sidh Gosṭi comprises seventy-three stanzas of which the first stanza consisting of four lines is by way of a prologue wherein Gurū Nānak is shown as discoursing with the Siddh Sabhā, i.e, assembly of the Siddhas, proclaiming that he paid obeisance to none other than the True Infinite One before whom everybody bows and who can be realized only with the aid of' a spiritual preceptor. He says that meditation on His Name was the only way to liberation and that the outer garb and wandering in search of Him were futile. After the first stanza in this section, there is a couplet which, marked as rahāu or pause, sums up the substance of the whole composition, i.e. renouncing the world and wandering in woods and mountains will be fruitless; it is through the True Name that life becomes pure and purposeful and one can attain emancipation. The three stanzas, numbering four to six, are designed as Gurū Nānak’s discourse with Charpaṭ, who belonged not to the Siddha but Nātha tradition which had evolved in protest against the former's over infatuation with supernatural powers which they generally used for the satisfaction of their carnal desires. Charpaṭ puts two questions to Gurū Nānak as to how successfully to swim across the ocean of life and how to realize God. Gurū Nānak’s reply is that one can achieve liberation by remaining detached while still living in the world and by making human heart a worthy abode for the Supreme Being by cleansing it of all impurities, and not by renouncing the world as did the Siddhas, Nāthas and Yogīs. Stanzas seven to eleven comprise Gurū Nānak’s dialogue with Lohārīpā, who proclaims the importance of renunciation, outer garbs and rituals in contradistinction to the former's stress on inner purity and self-control. Lohārīpā favours the austere life of Siddhas who lived amid shrubs and trees, away from the towns and highways subsisting on roots and underground bulbs. According to him, ablutions at a sacred place of pilgrimage brought man peace. Gurū Nānak rejects the significance of outer garb, renunciation of the world in favour of wandering in forests away from human habitation and visits to places of pilgrimage as the ultimate end of human life. He on the other hand recommends man to control his passions and fix his mind on Him who pervades throughout the universe which is His creation. What follows in stanza eleven is not Gurū Nānak’s discourse with any particular Siddha, but his recollection of some of the points from a dialogue he might have had with different Siddhas on different occasions. These cover a wide variety of subjects such as the definition of a true yogī, gurmukh and manmukh; the origin of the universe and of man; and the significance of truthfulness and of constant meditation on His Name in realizing the ultimate end of human life, i.e. emancipation from the process of transmigration and being one with the Supreme Being. According to Gurū Nānak, a yogī is not one who renouncing the world wanders in the woods and mountains, but one who effaces his self-conceit, becomes detached and enshrines the True Lord in his heart. As opposed to manmukh, i.e. the self-willed who assailed by doubt wanders in wilderness (26), the gurmukh, one who has his face and mind turned towards the Gurū, remains busy in reflecting on the gnosis and attains the invisible and infinite Lord (27). In answering the Siddhas' questions concerning the origin of the universe and man, Gurū Nānak refers to the concepts of śūnya (void) and śabda (word) also. Before the creation of man and the universe, there was no world, no firmament, yet it was not an empty void. The light of the Niraṅkār, i.e. the Formless Lord, pervaded the three worlds (67). Gurū Nānak’s śūnya, sunn in the text, does not mean nothing or an empty void. It is not a negative concept; rather it is a positive cause of the cosmos; it is nothing but the Brahman Himself. His śūnya is the emptiness of the vase, the essential intrinsic nature and quality of the pot. The word has also been used in the sense of Brahman, both with māyā and as pure Brahman when the Gurū says that śūnya is within us and without us and that the worlds are also imbued with śūnya. He who realizes the fourth state of śūnya remains unaffected by vice and virtue (51). Here the śūnya that envelops the three worlds is nothing but Brahman with māyā, the fourth state of śūnya being pure Brahman. In reply to a Siddha's question as to how the śūnya, i.e. Brahman is obtained and what is the state of those who are with the śūnya (Lord) imbued, Gurū Nānak replies that it is through the Gurū and by instructing the mind that the Imperishable Lord is obtained and that those who obtain Him are like Him from whom they have emanated and that they suffer not in the cycle of transmigration (52). A person knowing the mystery of God, who pervades all the hearts, himself becomes the manifestation of the Primal, Immaculate and Luminous Lord; one imbued with His Name is himself the Lord Creator (51). The śabda, which in gurbāṇī has been described more in terms of what it does than what it actually is, provides the means whereby man can know both God and the path that leads to Him, the means whereby man may secure release from bondage and attain union with Him. In Sidh Gosṭi, śabda (sabad) has been enlightenment, eternal delight and true yoga (32 and 33). Sublime understanding and shedding of lust, anger and ego are possible only with the help of śabda (10). It is through śabda that man is able to counteract the poison of ego and understand the true meaning of the creation and of the Creator (21). The śabda is competent to annul man's transmigration and secure him liberation (25). All the wanderings of yogī and saṅnyāsīs will come to naught if they fail to drop ego from their hearts (34) and ego, which hinders man's progression towards the Supreme Reality, can be effaced only through the śabda (21). In reply to a Siddhas' question as to where does śabda which helps man ferry across the ocean of life abide (58), Gurū Nānak says that it pervades all beings and that, if one is blessed with the Lord's grace, abides it in the human heart, dispels all doubt and leads one to union with the Supreme Lord (59).

        The language of the Sidh Gosṭi is Sādh Bhākhā with an admixture of technical terms from the disciplines of the Yogīs and the Siddhas. Brevity is chief characteristic of the style of expression. Symbols and metaphors used are more functional than decorative and have been taken from everyday life. The classical symbol of a lotus flower growing in water drawing its sustenance from the mud below and yet remaining untouched by it has also been used to illustrate the point that man can live a detached life in this world and realize the Supreme Lord by enshrining His Name in his heart. So has been the symbol of the duck swimming in water without wetting its wings.