“Then said Jesus again unto them, I go my way, and ye shall seek me, and shall die in your sins: whither I go, ye cannot come.”
King James Version (KJV)
8:19 Then said they to him, Where is thy Father? Jesus answered - Showing the perverseness of their question; and teaching that they ought first to know the Son, if they would know the Father. Where the Father is - he shows, #John 8:23|. Meantime he plainly intimates that the Father and he were distinct persons, as they were two witnesses; and yet one in essence, as the knowledge of him includes the knowledge of the Father.
8:23 Ye are - Again he passes over their interruption, and proves what he advanced, #John 8:21|. Of them that are beneath - From the earth. I am of them that are above - Here he directly shows whence he came, even from heaven, and whither he goes.
Joh 8:21 Whither I go, ye cannot come. Because they shall "die in their sins", and he will return to heaven, where the sinner cannot enter.