Note the different phrase, distinguishing the Jews from the mixed company in Joh 8:30. Rev., rightly, believed Him.
If ye continue (ἐὰν ὑμεῖς μείνητε)
The emphasis is on the ye, addressed to those whose faith was rudimentary; who believed Him, but did not yet believe on Him. Rev., abide.
In my word (ἐν τῷ λόγῳ τῷ ἐμῷ)
Literally, in the word which is mine: peculiarly mine, characteristic of me. The expression is intentionally stronger than my word. Compare my love (Joh 15:9).
Indeed (ἀληθῶς)
Literally, truly; as Rev. As those who believe on me, not as those who are moved by temporary excitement to admit my claims.