Given that the authenticity of the text for this week (John 7:53-8:11) is disputed, it is worthwhile to spend some time reflecting on the more general question of how we get the text of the New Testament. For good reason, you don’t often—or maybe even never—think about how the Scriptures of the Old and New Testament made their way into an English translation. Even more obscure for most is the matter of determining what are the Scriptures of the Old and New Testament. Included in this fairly technical matter are two broad areas of research. First, there is the study of the canon, or which books comprise the Scriptures. Second, there is the study of textual criticism in which the many manuscripts that contain some or all of the books of the Bible are compared and evaluated. It is to this second broad area of research that I want to turn now.
Our starting point is the plain fact that we do not possess, as far as we know, the original documents for any of the books of the Bible. These autographs, however, were shared and copied many times over, and then those copies were again shared and copied. Eventually, copies of books of the Bible, e.g. collections of Paul’s letters or the four gospels, were brought together in codices that are very similar to our modern books. By the 4th century AD, whole hand-copied New Testaments were being commissioned by Constantine.
Focusing on the text of the New Testament, more than 5,700 manuscripts have been discovered with some or all of the New Testament preserved on them. To be sure, most of these manuscripts provide only fragmentary, supporting evidence for the next of the New Testament, but at least 60 manuscripts contain the whole of the New Testament while many more contain at least all of the four gospels or all of Paul’s letters. While that might not sound like a tremendous number of copies to have survived, it is only a portion of the witness to the New Testament text, for there are many thousands more quotations of the New Testament from the writings of the early church fathers as well as very early translations into Syriac, Latin, Coptic, and other languages.
All that said, though we do not possess the original autographs, we possess numerous copies of them, some of which have been dated to the 2nd century (100-200 AD). For example, there are four slivers of 2nd century papyrus containing fragments from the gospels of Matthew, Mark, and John. Another 2nd century papyrus contains fragments of a few verses of Revelation 1. Extending into the 3rd century, there are eight more documents with fragments from the Gospels, Acts of the Apostles, and some of Paul’s letters. The earliest complete copies of the Bible come from the 4th century, and after the 4th century we have numerous copies of high quality that nevertheless highlight the variety of exclusions and additions that one would expect from centuries of hand copying.
But, while the variety of readings of a given New Testament book, chapter, and verse might sound troubling, it is actually quite helpful. Because of the numerous copies that we possess, they can be compared with one another in such a way that exclusions or additions to the text can be fairly easily identified. In truth, we possess more than the contents of the New Testament, and the work of textual criticism is to identify the patterns of exclusions, additions, and mistakes so that the text of the New Testament can be preserved.
All of this leads us to John 7:53-8:11, for its authenticity is determined at least in part through an investigation of its presence or absence in the thousands of copies of the New Testament that we possess. As far as the data are concerned, “The account is lacking in the best Greek manuscripts,” including the two 4th century codices, but “even more significant is the fact that no Greek Church father for 1,000 years after Christ refers to the pericope as belonging to the fourth Gospel, including even those who … dealt with the entire Gospel verse by verse.” Even in many of the later manuscripts that do include the story, it is marked off—like it is in the ESV and NIV—as an indication that its presence is controversial.
In the end, the point is that we have good reasons and great resources for judging the authenticity of the text of the New Testament, including the story of the adulterous woman. Therefore, when you pick up your Bible, you have very good reason to believe that you are reading the Word of God.
 Bruce M. Metzger and Bart D. Ehrman, The Text of the New Testament: Its Transmission, Corruption, and Restoration, 4th ed. (New York: Oxford University Press, 2005), 15.  Metzger and Ehrman, The Text of the New Testament, 50–51.  https://manuscripts.csntm.org/Manuscript  Metzger and Ehrman, The Text of the New Testament, 319.  Metzger and Ehrman, The Text of the New Testament, 320.