Vivasvān is the Sun — literally “the one who shines forth,” the luminous source that sustains all life on earth. That Kṛṣṇa should give this Yoga first to the Sun is fitting: a teaching meant to enliven the whole world is handed to the enlivener of the whole world. From Vivasvān it passes to Manu (the archetypal first man and law-giver) and to Ikṣvāku (founder of the solar dynasty), and so down a chain of royal sages. This chain is the paramparā — the unbroken hand-to-hand succession by which a living teaching is transmitted, not as dead text but from a realised teacher to a ready student. The point is subtle: the truth is timeless, but its transmission is fragile, and “by long lapse of time this Yoga was lost.” That is why it must, from age to age, be spoken again.