That is why I told you that you will die in your sins: if you do not believe that I am he, you will die in your sins.”
In context
22So the Jews said, “He isn’t going to kill himself, is he? Is that why he says, ‘Where I am going, you cannot come’?” 23He said to them, “You are from below; I am from above. You belong to this world; I do not belong to this world. 24That is why I told you that you will die in your sins: if you do not believe that I am he, you will die in your sins.” 25“Who are you?” they asked. Jesus said to them, “What I have been telling you from the beginning. 26There is much I could say about you, and much to judge. But the one who sent me is true, and what I have heard from him — that is what I tell the world.”