44 Or (perhaps) “I am certainly telling you this.” According to §12.3 ἀπʼ ἄρτι (ap’ arti) should be read as ἀπαρτί (aparti), meaning “exactly, certainly.”
45 Grk “so that you may believe.”
46 Grk “that I am.” R. E. Brown (John [], 2:) argues for a nonpredicated ἐγώ εἰμι (egō eimi) here, but this is far from certain.

In other versions

I am telling you this now, before it takes place, that when it does take place you may believe that I am he.

“I am telling you now before it happens, so that when it does happen you will believe that I am who I am.

I am telling you now before it happens, so that when it does happen you will believe that I am he.

I tell you this beforehand, so that when it happens you will believe that I Am the Messiah.

From now on I am telling you before it happens, in order that when it happens you may believe that I am he.

Now I tell you before it come, that, when it is come to pass, ye may believe that I am he.

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