It is quite rare that new textual evidence is published which could make a significant difference to how a New Testament passage is translated. Peter Rodgers, writing at Evangelical Textual Criticism, seems to have found a possible example.
It seems that a newly published papyrus fragment, P125, includes at 1 Peter 2:3 the reading christos “Christ, Messiah”, where the standard critical text has chrēstos “good, kind”. The fragment is significant because it is one of the oldest surviving for this passage, from the late third or early fourth century. The reading christos is found in some quite late manuscripts and in the one other papyrus witness for this text, P72, from the same period as P125. But the great uncial codices of the late fourth and fifth centuries (Sinaiticus, Vaticanus and Alexandrinus) agree with the Byzantine majority text in reading chrēstos.
One thing to note here is that the words christos and chrēstos were very often confused because in the New Testament and later periods they were pronounced almost identically. Secular authors may have misunderstood the religious term christos as chrēstos, but Christian copyists would have tended to replace chrēstos with christos. Textual critics used to judge that the latter is what had happened to late manuscripts with christos. The reading later discovered in P72, published in 1959, was presumably considered to be an oddity. But now it has been confirmed, as there are, in Rodgers’ words,
two papyri from different places in Egypt [which] give different abbreviations of Christos.
And so a strong argument can now be made that christos is the original reading.
Part of that argument would have to be that the uncial and Byzantine reading chrēstos has been harmonised with the Greek version of Psalm 34:8 (numbered 33:9 in LXX). This has chrēstos, as an accurate rendering of Hebrew tov “good”. Copyists could easily have assumed that the Apostle Peter was simply quoting LXX, or providing his own accurate translation of the psalm into Greek, and so corrected christos to chrēstos.
But there was something more going on here. The apostle was surely aware of the similarity in sound between christos and chrēstos, and deliberately making use of this in his letter As Rodgers writes,
Christos in 1 Peter 2:3 is not a patristic but a petrine pun.
Peter surely noticed that the words in the psalm, read out in Greek, sounded just like christos ho kurios, meaning “the Lord is Christ”, a variant of the basic Christian confession “Christ is Lord” which had just been made by the new believers he was addressing. So, very likely, he deliberately adapted his psalm quotation to bring this out. We cannot be sure which of the words Peter actually wrote down, but it does at least seem clear that he intended to make a pun here.
So, how should we see this reflected in translations? The new evidence Rodgers quotes might be enough to justify a change in this verse to “you have tasted that the Lord is Christ”. But that rendering obscures the pun just as much as the more traditional “… the Lord is good”. There is no one English word which even by according to its sound means both “Christ” and “good”. So this is a case where translators really need to choose one rendering for the text and mention the other in a footnote.