43 Grk “He”; the referent (Jesus) has been specified in the translation for clarity.
44 The expression οὖν πάλιν (oun palin) indicates some sort of break in the sequence of events, but it is not clear how long. The author does not mention the interval between 8:12–20 and this next recorded dialogue. The feast of Tabernacles is past, and the next reference to time is 10:22, where the feast of the Dedication is mentioned. The interval is two months, and these discussions could have taken place at any time within that interval, as long as one assumes something of a loose chronological framework. However, if the material in the Fourth Gospel is arranged theologically or thematically, such an assumption would not apply.
45 Grk “you will seek me.”
46 The expression ἐν τῇ ἁμαρτίᾳ ὑμῶν ἀποθανεῖσθε (en tē hamartia humōn apothaneisthe) is similar to an expression found in the at Ezek 3:18, 20 and Prov 24:9. Note the singular of ἁμαρτία (the plural occurs later in v. 24). To die with one’s sin unrepented and unatoned would be the ultimate disaster to befall a person. Jesus’ warning is stern but to the point.

In other versions

So he said to them again, “I am going away, and you will seek me, and you will die in your sin. Where I am going, you cannot come.”

Once more Jesus said to them, “I am going away, and you will look for me, and you will die in your sin. Where I go, you cannot come.”

Then he said to them again, “I’m going away; you will look for me, and you will die in your sin. Where I’m going, you cannot come.”

Later Jesus said to them again, “I am going away. You will search for me but will die in your sin. You cannot come where I am going.”

So he said to them again, “I am going away, and you will seek me and will die in your sin. Where I am going you cannot come!”

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.

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