BG 4.2

This supreme science was thus received through the chain of disciplic succession, and the saintly kings understood it in that way. But in course of time the succession was broken, and therefore the science as it is appears to be lost.

4.2. Thus the regal sages knew this, received in regualr succession. By the passage of long time, this Yoga has been however lost, O scorcher of enemies !

4.2 The Divine Kings knew it, for it was their tradition. Then, after a long time, at last it was forgotten.

4.2 See Comment under 4.3

4.1 - 4.2 The Lord said This Karma Yoga declared to you should not be considered as having been taught now merely, for creating encouragement in you for war. I Myself had taught this Yoga to Vivasvan at the commencement of Manu's age as a means for all beings to attain release, which is man's supreme end. Vivasvan taught it to Manu, and Manu to Iksvaku. The royal sages of old knew this Yoga transmitted by tradition. Because of long lapse of time and because of the dullness of the intellect of those who heard it, it has been almost lost.

4.2 Rajarsayah, the king-sages, those who were kings and sages (at the same time); viduh, knew; imam, this Yoga; which was evam parampara-praptam, received thus through a regular succession of Ksatriyas. Sah, that; yogah, Yoga; nastah, is lost, has go its traditional line snapped; iha, now; mahata kalena, owing to a long lapse of time. parantapa, O destroyer of foes. By para are meant those against oneself. He who, like the sun, 'scorches' (tapayati) them by the 'rays' of the 'heat' of his prowess is parantapa, i.e. scorcher of antagonists. Noticing that the Yoga has got lost by reaching people who are weak and have no control of their organs, and that the world has become associated with goals that do not lead to Liberation,

4.2 Thus handed down in succession, the royal sages knew this (Karma Yoga). But with long lapse of time, O Arjuna, that Yoga was lost to the world.

4.2 The king-sages knew this (yoga) which was received thus in regular succession. That Yoga, O destroyer of foes, in now lost owing to a long lapse of time.