John 8:21-24

Once more Jesus said to them, "I am going away, and you will look for me, and you will die in your sins. Where I go you cannot come." This made the Jews ask, "Will he kill himself? Is that why he says, 'Where I go you cannot come'?" But he continued, "You are from below; I am from above. You are of this world; I am not of this world. I told you that you would die in your sins; if you do not believe that I am he, you will indeed die in your sins."

you will look for me, and you will die in your sins 
Ezekiel 3:18-19  "When I say to a wicked person, 'You will surely die,' and you do not warn them or speak out to dissuade them from their evil ways in order to save their life, that wicked person will die for their sin, and I will hold you accountable for their blood. But if you do warn the wicked person and they do not turn from their wickedness or from their evil ways, they will die for their sin; but you will have saved yourself."

Where I go, you cannot come 
John 7:33-34  Jesus said, "I am with you for only a short time, and then I am going to the one who sent me. You will look for me, but you will not find me; and where I am, you cannot come."
John 13:33  "My children, I will be with you only a little longer. You will look for me, and just as I told the Jews, so I tell you now: Where I am going you cannot come."

You are of this world; I am not of this world 
John 3:31  The one who comes from above is above all; the one who is from the earth belongs to the earth, and speaks as one from the earth. The one who comes from heaven is above all.
John 17:14-16  "I have given them your word and the world has hated them, for they are not of the world any more than I am of the world. My prayer is not that you take them out of the world but that you protect them from the evil one. They are not of the world, even as I am not of it."

if you do not believe that I am he, you will indeed die in your sins 
John 4:26  Then Jesus declared, "I, the one speaking to you--I am he."
John 13:19  "I am telling you now before it happens, so that when it does happen you will believe that I am who I am."

Scriptures taken from the Holy Bible, New International Version® NIV®, 
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