Within Vajrayāna, the tantras function as the foundational scriptural basis for esoteric doctrine and practice. They articulate the distinctive worldview of the tantric path, setting forth the philosophical framework for deity yoga, subtle body practices, and the transformation of ordinary experience into enlightened awareness. Concepts such as mandala, initiation, and the subtle channels and energies are embedded in these texts, which serve as the canonical reference point for what counts as authentically tantric. In this way, the tantras provide not only teachings but also the criteria by which those teachings are recognized and validated.

At the same time, tantras operate as detailed practice manuals and ritual blueprints. They present specific instructions for visualizations, mantras, mudrās, offerings, and the sequence of ritual actions, often focusing on particular deities and their associated methods. From these root and explanatory tantras arise sādhana texts and liturgies that shape daily practice, retreats, and the broader ritual life of practitioners. The classification of different levels and types of tantra creates a structured curriculum, allowing practices to be organized according to the practitioner’s capacity and stage of development.

The authority of tantric practice is inseparable from lineage and initiation, and here the tantras play a decisive role. They themselves mandate the necessity of empowerment, scriptural transmission, and oral instruction from a qualified teacher, and they often include directions on how the teachings are to be passed down. A practice is regarded as legitimate when it can be traced to a specific tantra and through an unbroken human lineage of transmission. In this sense, the texts are both repositories of esoteric knowledge and instruments that safeguard the continuity and authenticity of the tradition.

Yet the tantras are deliberately not self-explanatory. They frequently employ symbolic or “twilight” language and encode higher yogic methods in ways that are inaccessible without oral commentary. This ensures that the deepest instructions remain dependent on a living relationship with a guru, who unlocks the layered meanings and adapts them to the disciple’s understanding. The texts thus preserve and transmit Vajrayāna teachings across generations, while simultaneously ensuring that their transformative power is activated only through proper initiation, guidance, and disciplined practice.