Lord Krishna said: I first imparted this imperishable spiritual science (yoga) to Vivasvan. Vivasvan told Manu about it; and Manu spoke to Ikshvaku.
Though Krishna had concluded his message in the 2nd chapter, Arjuna’s doubt extended the dialogue. Krishna clarified it satisfactorily. And as was the custom, narrated the lineage relating to the message, marking the finale of the instruction.
Krishna says he first imparted this science to Vivasvan, the predecessor of Manu, the first human on the planet. He, in turn transmitted it to Ikshvaku, the ancestor of the Solar dynasty that ruled India for long. Thus the legacy dates back to the origin of humanity as well as the planet we are living in. Yes, Brahmavidya is ageless!