Arjuna pauses and does what any honest listener would do — he asks. Your birth is recent, Krishna. The Sun god Vivasvan belongs to a time beyond memory. How can I accept that You taught him at the very beginning? The question carries no disrespect. It is the genuine puzzlement of someone trying to reconcile what he sees with what he hears.
This is one of those rare moments in the Gita where Arjuna speaks not as a warrior seeking guidance, but as a friend seeking understanding. He trusts Krishna enough to voice his confusion openly.
And this simple question opens a door to one of the Gita's greatest revelations — the mystery of divine incarnation. The next two shlokas will explain the difference between how an ordinary soul is born and how the Lord manifests in the world.