While, studying Jude 1:5 in Accordance 11. I noticed, that the Nestle-Aland Greek New Testament 28th edition has ‘Jesus’ in place of ‘Lord’ used in the Textus Receptus (as well as the vast majority of printed Greek New Testament editions) . The ESV and the NET follow the reading of 28th edition of the NA (or the apparatus of the 27th edition), while Translations like the KJV and NIV have Lord. Of, course the KJV is following one of the western TR’s (not actually the byzantine majority textual tradition, but only what was know of it in old Europe) .
According to Late Greek Scholar Metznger the previous edition of the NA (the 27th edition) did not adopt ὁ Ἰησοῦς into the main text because:
"Despite the weighty attestation supporting Ἰησοῦς (A B 33 81 322 323 424c 665 1241 1739 1881 2298 2344 vg cop, bo eth Origen Cyril Jerome Bede; ὁ Ἰησοῦς 88 915), a majority of the Committee was of the opinion that the reading was difficult to the point of impossibility, and explained its origin in terms of transcriptional oversight (ΚΧ being taken for ΙΧ). It was also observed that nowhere else does the author employ Ἰησοῦς alone, but always Ἰησοῦς Χριστός. The unique collocation θεὸς Χριστός read by P72 (did the scribe intend to write θεοῦ χριστός, “God’s anointed one”?) is probably a scribal blunder; otherwise one would expect that Χριστός would be represented also in other witnesses.
The great majority of witnesses read ὁ before κύριος, but on the strength of its absence from א Ψ and the tendency of scribes to add the article, it was thought best to enclose ὁ within square brackets.
[Critical principles seem to require the adoption of Ἰησοῦς, which admittedly is the best attested reading among Greek and versional witnesses (see above). Struck by the strange and unparalleled mention of Jesus in a statement about the redemption out of Egypt (yet compare Paul’s reference to Χριστός in 1 Cor 10:4), copyists would have substituted (ὁ) κύριος or ὁ θεός. It is possible, however, that (as Hort conjectured) “the original text had only ὁ, and that οτιο was read as οτι ΙΧ and perhaps as οτι ΚΧ” (“Notes on Select Readings,” ad loc.).”
Bruce Manning Metzger, United Bible Societies, A Textual Commentary on the Greek New Testament, Second Edition a Companion Volume to the United Bible Societies’ Greek New Testament (4th Rev. Ed.) (London; New York: United Bible Societies, 1994), 657–658.
ὁ Ἰησοῦς was indeed the reading that was difficult, because of the use of definite article with name Ἰησοῦς and the lack of Χριστός makes it pretty difficult for anyone to accept.
The exact linear string ὁ Ἰησοῦς (that’s the definite article nominative masculine singular immediately followed by Jesus noun nominative masculine singular proper) appears 280 times mostly in the Gospels and three times in the book of Acts. Outside, of Acts this linear string simply does not occur in writings of Paul, Peter, John, or Jude in what have been the standard printed Greek New testaments and in the standard morphological Greek NT.
But, note: rather than accepting ὁ Ἰησοῦς the editors of the NA 28 edition actually went with ὅτι Ἰησοῦς maybe a compromise? This phrase appears in the following passages:
Matthew 20:30, Mark 10:47, Luke 18:37, John 4:1, John 4:47, John 5:15, John 6:24, John 7:39
John 11:20, John 20:14, John 20:31, John 21:4, Acts 6:14, 2 Corinthians 13:5, 1 Thessalonians 4:14, 1 John 2:22,1 John 4:15, 1 John 5:1, 1 John 5:5, and now in Jude 1:5
While, the title Lord(kurious) can be used for honorable persons in this context it is pretty clear that the Lord(Kurious) used refers to YHWH leading his people out of Egypt. Sometimes scribes did make mistakes especially with words that look or sound similar, but Lord(Kurious) and Jesus (Yesous) sound and look so different that it is hard for me to believe this was simply a slip of hand.