There are three subjects you touch on:
- Consistency between different Bible manuscripts
- Consistency between how any given Bible translation handles the manuscript(s) upon which it is based
- The nature of infallibility, as it relates to Scripture
Consistency between Bible manuscripts
The King James translators consulted primarily a set of Greek manuscripts that were published during the 16th century by Erasmus, a Dutch scholar. Erasmus compiled his manuscripts, which date from the 12th through the 15th century, mostly from a collection made available to him by Roman Catholic Dominican friars in Basel, Switzerland.
Other translations utilized different sets of Greek manuscripts. Contemporary to Erasmus was a compendium known as the Complutensian Polyglot, backed by the Spanish Cardinal Francisco Jiménez de Cisneros. Various other Greek manuscript sets, all confusingly referred to individually as Textus Receptus, continued to be published through the 19th century.
Altogether, there are over 5,000 Greek manuscripts of the New Testament, ranging from small fragments to complete texts. The various manuscripts differ in the verse you cite: the majority include the word σοφῷ, but many important "witnesses" (e.g. Codex Sinaiticus, Codex Alexandrinus, Codex Vaticanus) do not.
For the past several decades, a so-called "eclectic" Greek text - the Nestle-Aland - that pieces together individual verses from multiple manuscripts has been the basis for many New Testament translations, including the RSV, NRSV, and ESV. Some editions have chosen to piece together their own particular eclectic texts (e.g. NIV, NASB). The Nestle-Aland recently underwent its 28th revision since originally being published in 1898 (then just the "Nestle"). The United Bible Society publishes a version of the Nestle-Aland text with an apparatus that cites Greek variants of each verse. It shows that there are 4 places in just Jude 25 alone where words are either omitted in one place from one manuscript to another or different words are used. The UBS apparatus implies that Jude 25 could be reconstructed 16 different ways from the available manuscripts. The situation is very similar for the majority of verses in the Greek text.
So first, we must acknowledge that in the Greek sources that are available to us today, there are countless disparities.
Consistency between how any given Bible translation handles the manuscript(s) upon which it is based
As you will see many others here explain, translations veer toward one of two styles: dynamic equivalence and formal equivalence. These could be loosely termed free-form and literal. Because there are such great differences in syntax and grammar, translating each word of the Greek word for word would render nonsense in many cases. In our list KJV is close to a formally equivalent translation, whereas the GNT would be termed a dynamically equivalent translation. In either case, one should probably never expect two different translations from Greek into the same language to use exactly the same words everywhere, even if they are consulting identical manuscripts.
The nature of infallibility, as it relates to Scripture
Not all Christians, nor even Jews, I think, agree on how or to what degree Scripture is infallible. We have already seen that there are many, many inconsistencies in manuscripts (though many of these are very minor), but even placing issues of manuscripts and tradition aside there are factual inconsistencies throughout both the Old and the New Testament. Some of these are self-evident. It is supposed, for example, that Jesus spoke Aramaic and not Greek to his fellow Jews, yet the Gospels, written in Greek, depict Him speaking Greek. If one were to insist on absolute Biblical infallibility in all respects, one would have to convince oneself that Jesus only spoke Greek, except for rare exceptions, as He spoke to Jews throughout Judea, Samaria, and Galilee during the course of his earthly life.
Perhaps surprising to some, earlier Christians were not particularly troubled by this. A reflection on this can be found at the beginning of the 4th century homilies on Matthew composed by John Chrysostom:
But the contrary, it may be said, has come to pass, for in many places
they are convicted of discordance. Nay, this very thing is a very
great evidence of their truth. For if they had agreed in all things
exactly even to time, and place, and to the very words, none of our
enemies would have believed but that they had met together, and had
written what they wrote by some human compact; because such entire
agreement as this comes not of simplicity. But now even that
discordance which seems to exist in little matters delivers them from
all suspicion, and speaks clearly in behalf of the character of the
But if there be anything touching times or places, which they have
related differently, this nothing injures the truth of what they have
said. And these things too, so far as God shall enable us, we will
endeavor, as we proceed, to point out; requiring you, together with
what we have mentioned, to observe, that in the chief heads, those
which constitute our life and furnish out our doctrine, nowhere is any
of them found to have disagreed, no not ever so little.
But what are these points? Such as follow: That God became man, that
He wrought miracles, that He was crucified, that He was buried, that
He rose again, that He ascended, that He will judge, that He has given
commandments tending to salvation, that He has brought in a law not
contrary to the Old Testament, that He is a Son, that He is
only-begotten, that He is a true Son, that He is of the same substance
with the Father, and as many things as are like these; for touching
these we shall find that there is in them a full agreement.
(Most of the material above, except for the quote from John Chrysostom - which is available at ccel.org - come from Wikipedia, the UBS edition I refer to, or Metzger's Textual Commentary on the New Testament.)