The Aatma is neither born, nor does it die. No sword can cut it and no fire can burn it. You are that, which is eternal. Then, why do you worry? Whom do you fear? Who can kill you?
Change is the law of the universe but this physical body is not the real you. The body will age and will return to nature’s elements when it dies. But the Atman is eternal. So, who are you?