The first module presents a brief history of the meaning of haṭhayoga (“the yoga of force”) in Buddhist tantras, where it appears as an auxiliary method of ṣaḍaṅgayoga during the perfection stage (utpannakrama) of the Niruttaratantras. The earliest text to mention the method of haṭhayoga is one of the foundational Buddhist tantras, the Guhyasamājatantra (8th century CE). Nāropa (956–1040), one of the most influential figures in Buddhist tantric traditions, offers a detailed account of this technique in the Paramārthasaṃgraha, his important commentary on the Sekoddeśa (a chapter of the lost Kālacakramūlatantra). The module includes close reading and discussion of relevant passages from Nāropa and other commentators in which this forceful method is described with particular precision. It also introduces the Six Yogas of Nāropa, highlighting the similarities between certain practices—especially gtum mo (inner heat) and ’pho ba (the transference of consciousness)—and the technical explanations of haṭhayoga and nādābhyāsa found in Buddhist tantric literature.

This module examines the authors associated with the Amṛtasiddhi exegetical cycle, beginning with the semi-mythical figure of Virūpa, one of the eighty-four Buddhist mahāsiddhas. Recent research suggests possible connections between the Buddhist Virūpa and Virūpākṣa of the Nāth Śaiva tradition, particularly in the southern Konkan, where historical sources indicate a transition from Vajrayāna Buddhism to Nāth Śaivism. This context helps illuminate the movement of yogic techniques from a tantric Buddhist milieu into later Śaiva traditions. The module also considers the historical figures Amoghavajra and Dur khrod pa (Eṇadeva), including the debated identification of Eṇadeva with the so-called “Black Virūpa.” Vanaratna (1384–1468), the last great Indian paṇḍit active in Tibet, is briefly discussed for his role in re-translating related materials into Sanskrit. While the Amṛtasiddhi itself may not have achieved broad prominence in Tibet as a textual tradition, closely related practices—known as rtsa lung ’khrul ’khor (the training of channels and winds) and associated with lineages such as those of Tilopa (c. 928–1009), Nāropa (956–1040), and others—are widely observed across Tibetan tantric traditions, including the Gsar ma, Rnying ma, and Bon schools.

The third module analyses the central doctrine of the Amṛtasiddhi, highlighting its Buddhist tantric elements, such as the definition of bindu as seminal fluid—also found in the Kālacakratantra tradition—the doctrine of the four blisses, and the ritual retention of semen during the sexual rite. The module also explores connections with Chinese internal neidan alchemy.

The fourth module turns to the physical practices of the Amṛtasaṁkaṭanibarhaṇa, beginning with an analysis of the thirty-six obstacles. These obstacles offer a particularly rich and detailed articulation of the Vajrayāna conceptual framework, reflecting key aspects of Buddhist tantric thought, including ethical foundations, anti-intellectualism, and critiques of dogmatism and scholasticism. The module then examines the physical practices of ’khrul ’khor (yantra). It considers the meaning of the term yantra in light of the Paramākṣajñānasiddhi, an alchemical text preserved within the Kālacakratantra tradition that displays alchemical parallels with the Amṛtasiddhi. The module then analyses the postural and dynamic practices presented in the Amṛtasaṁkaṭanibarhaṇa. Many of these practices are strikingly similar to āsanas found in later Indian haṭhayoga literature. Together, these examples show how the Amṛtasaṁkaṭanibarhaṇa may be regarded as one of the earliest manuals in Indian and Tibetan yoga literature to present a forceful method of dynamic physical yoga.