1 Yohanes 2:23

2:23 Everyone who denies the Son does not have the Father either. The person who confesses the Son has the Father also. ¹ 

1 Yohanes 5:21

5:21 Little children, guard yourselves from idols. ² 

[2:23]  ¹ tc The Byzantine text, almost alone, lacks the last eight words of this verse, “The person who confesses the Son has the Father also” (ὁ ὁμολογῶν τὸν υἱὸν καὶ τὸν πατέρα ἔχει, Jo Jomologwn ton Juion kai ton patera ecei). Although shorter readings are often preferred (since scribes would tend to add material rather than delete it), if an unintentional error is likely, shorter readings are generally considered secondary. This is a classic example of such an unintentional omission: The τὸν πατέρα ἔχει of the preceding clause occasioned the haplography, with the scribe’s eye skipping from one τὸν πατέρα ἔχει to the other. (Readings such as this also suggest that the Byzantine text may have originated [at least for 1 John and probably the general epistles] in a single archetype.)

[5:21]  ² tc Most later mss (P Ï) have ἀμήν (amhn, “amen”) at the end of this letter. Such a conclusion is routinely added by scribes to NT books because a few of these books originally had such an ending (cf. Rom 16:27; Gal 6:18; Jude 25). A majority of Greek witnesses have the concluding ἀμήν in every NT book except Acts, James, and 3 John (and even in these books, ἀμήν is found in some witnesses). It is thus a predictable variant. Further, the earliest and best witnesses, along with several others (א A B Ψ 33 323 630 1505 1739 al sy co), lack the inoffensive particle, rendering its omission as the authentic reading.

[5:21]  sn The modern reader may wonder what all this has to do with idolatry. In the author’s mind, to follow the secessionist opponents with their false Christology would amount to idolatry, since it would involve worshiping a false god instead of the true God, Jesus Christ. Thus guard yourselves from idols means for the readers to guard themselves against the opponents and their teaching.