This verse establishes a foundational principle within the Yājñavalkya Yoga, asserting that true vrata – a sacred observance, a commitment – is derived not solely from textual authority, but from a synthesis of Vedic, Purāṇic, and smṛti traditions, illuminated by the direct teachings of a qualified guru. The emphasis on the ‘words of the guru’ is crucial; it signifies that knowledge, even when sourced from revered sources like the veda, purana, and smriti composed by great sages, must be filtered through the experiential guidance of one who has mastered the underlying principles. The combination of this inherited wisdom with the immediate, practical instruction of a guru constitutes the core of the vrata, a dedicated undertaking leading to spiritual realization. This highlights the importance of transmission and the embodied knowledge essential for navigating the complex path of yoga, a path rooted in both established doctrine and dynamic, personalized practice.