Thou seest Me as Time who kills,
Arjuna has received divine sight and beholds Krishna’s Vishvarupa — the universal form containing all creation, all destruction, all time. Terrified, he sees warriors being devoured by Krishna’s flaming mouths. He asks: who are you in this terrible form? Krishna answers: I am Time, destroyer of worlds. These warriors are already slain — be my instrument.
Famously paraphrased by Oppenheimer at Trinity: "Now I am become Death, the destroyer of worlds." The climax of the Gita’s cosmic vision.