Short answer
Scholars estimate between 200,000 and 400,000 differences among the New Testament copies. That is more than the number of words in the New Testament. Over 5,000 hand-written Greek copies survive, and about 10,000 in Latin. Most differences are small slips. But some are whole passages. Examples are the only verse that says the Father, the Word and the Holy Spirit are one, and the last twelve verses of Mark. The Old Testament copies and translations also disagree in thousands of places. One verse about King Saul has lost a number, and three Bibles print it three different ways. So no one can show that today's Bible reads word for word as it was first written. The Qur'an says God (﷾) Himself guards it from corruption.
Full explanation
Who counted the differences
The figures come from Bart Ehrman, a well-known expert on the hand-written copies (manuscripts) of the New Testament. He is not a Muslim. As a teenager he became an evangelical Christian, one who treats the Bible as the final authority. He learned Greek so that he could read the New Testament in its first language. He studied under Bruce Metzger, the leading scholar of the New Testament text in his day. He did not set out to find what he found about the copies. He reports 200,000 to 400,000 differences among the manuscripts, more than the words of the New Testament itself.
Ehrman, who became a committed evangelical as a teenager and studied at Moody Bible Institute and Wheaton before his doctorate under Bruce Metzger at Princeton Theological Seminary, reports that more than 5,700 Greek manuscripts of the New Testament are known, besides about 10,000 in Latin. No two are exactly alike. Estimates of the differences among them run from 200,000 to 400,000 or more, so that there are more differences among the manuscripts than there are words in the New Testament. Most are immaterial slips such as spelling; some change the meaning of a passage. Most surviving copies are centuries later than the originals, and the earliest are few and mostly fragments.
Three passages the earliest copies lack
Some differences are not slips of the pen. The first is 1 John 5:7. It is the only verse in the Bible that says the Father, the Word and the Holy Spirit are one. No Greek manuscript before the late Middle Ages has it, except as a later note in the margin. The second is the last twelve verses of Mark, with what Christians tell of the risen Jesus' appearances. They are missing from the two oldest Greek Bibles that survive in large part. Those end at verse 8, with the women afraid. The third is the story of the woman taken in adultery, in John. It is missing from the earliest copies of John, and later copies put it in different places, some in Luke. Christian scholars established all three points. Modern Bibles leave these passages out or mark them as doubtful.
“For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one.”
On 1 John 5:7-8, reports that the words about the Father, the Word and the Holy Spirit are absent from every known Greek manuscript except eight late ones, four of which have them written in the margin as a later addition; that no Greek church father quotes them; and that every ancient translation except the Latin lacks them.
“And they went out quickly, and fled from the sepulchre; for they trembled and were amazed: neither said they any thing to any man; for they were afraid.”
“Now when Jesus was risen early the first day of the week, he appeared first to Mary Magdalene, out of whom he had cast seven devils.”
On Mark 16:9-20, reports that the last twelve verses are absent from the two oldest Greek Bibles that survive in large part, Codex Sinaiticus and Codex Vaticanus, and from other early witnesses; that Eusebius and Jerome state the verses were missing from almost all the Greek copies known to them; that some manuscripts carry a different, shorter ending instead; and concludes that the Gospel as we have it from the earliest evidence ends at 16:8.
“So when they continued asking him, he lifted up himself, and said unto them, He that is without sin among you, let him first cast a stone at her.”
On the story of the woman taken in adultery (John 7:53-8:11), reports that it is absent from the early papyri (P66 and P75), from Codex Sinaiticus and Codex Vaticanus and other early witnesses, and that the manuscripts which do carry it place it in different spots: after John 7:52, after John 7:36, at the end of John, or after Luke 21:38. Concludes that it was no part of the original Gospel of John.
The Old Testament copies disagree too
The oldest complete Hebrew Bible that survives today is a copy made about 1008 CE. That is more than a thousand years after its latest book. The Dead Sea Scrolls were found starting in 1947. These older copies showed several forms of the text in use at once. The Samaritan Torah (the Samaritans' own copy of the five books of Moses) differs from the Jewish text in about 6,000 places. The Greek translation that the New Testament writers usually quote has a Jeremiah about a seventh shorter than the Hebrew. The ages in Genesis 5 and 11 differ between the Hebrew, the Greek and the Samaritan. The three date the Flood centuries apart. At 1 Samuel 13:1 the Hebrew has lost Saul's age. Three public-domain Bibles (ones anyone may copy freely), shown below, print the verse three different ways.
The standard handbook on the text of the Hebrew Bible. The oldest complete Hebrew Bible that survives is the medieval Leningrad Codex (1008-1009 CE). The Scrolls show the scriptures circulating in several different text forms around the turn of the era. The Samaritan Pentateuch differs from the Jewish Masoretic text in about 6,000 places; the Greek Septuagint's Jeremiah is shorter than the Hebrew by about one-seventh and orders its chapters differently, and its Job is about a sixth shorter. The ages in the genealogies of Genesis 5 and 11 differ between the three texts, so their chronologies of the Flood and the creation differ by centuries.
“Saul reigned one year; and when he had reigned two years over Israel,”
“Saul was thirty years old when he became king, and he reigned over Israel forty-two years.”
“Saul was a—years old when he began to reign; and two years he reigned over Israel.”
The Bible's text in numbers
- More than 5,000 hand-written Greek copies of the New Testament survive, and about 10,000 in Latin.
- Scholars estimate 200,000 to 400,000 differences among them. That is more differences than there are words in the New Testament.
- Most of the differences are small slips, such as spelling. But some are whole passages, such as the last twelve verses of Mark.
- The oldest complete Hebrew Bible that survives was copied about 1008 CE, more than a thousand years after its latest book.
- The Greek translation that the New Testament writers usually quote has a book of Jeremiah about a seventh shorter than the Hebrew.
- The ages in Genesis 5 and 11 differ between the Hebrew, the Greek and the Samaritans' own copy of the five books of Moses. So the three date the Flood centuries apart.
The Book God (﷾) promised to guard
The Qur'an says God (﷾) sent it down and will guard it from corruption. It also invites the reader to test it: if it were from anyone but God (﷾), people would find much discrepancy in it. Many people memorised it in the lifetime of the Prophet (ﷺ). Scribes whose names are known wrote it down. Many of those who knew it by heart were later killed in battle. Then Zayd ibn Thabit gathered it into one volume from the written pieces and from the memorisers. He had written down the revelation for the Prophet (ﷺ).
“We have, without doubt, sent down the Message; and We will assuredly guard it (from corruption).”
“Do they not consider the Qur'an (with care)? Had it been from other Than Allah, they would surely have found therein Much discrepancy.”
Zayd ibn Thabit reports that after many who knew the Qur'an by heart were killed at Yamama, Abu Bakr asked him to gather the Qur'an into one volume, reminding him that he used to write down the revelation for the Messenger of Allah. Zayd collected it from written pieces and from the memories of men, and the finished copy passed from Abu Bakr to Umar and then to Hafsa.
The reply Christians give
The New Testament in the Original Greek: Introduction (1882)
The classic statement of the defence. Leaving aside differences of spelling, the editors of the critical Greek text judge that the words still open to doubt make up about a sixtieth of the New Testament, that most of these are comparatively trivial, and that substantial variation can hardly amount to more than a thousandth part of the text.
Cited for
Christians answer that most of these differences are spelling, word order or a dropped word, and change nothing that matters.
The response
Most are small, and nobody claims 400,000 differences mean 400,000 doctrines. But the three passages above are not slips. They carry the Trinity, the resurrection appearances in the earliest Gospel, and a famous story of Jesus. The same hand-copying that produced the small slips also carried doctrine into the text. These three were caught only because older copies survive.
Where it lands — Most differences are small, but the three passages show that the copying changed doctrine too.
Perspectives
Mainstream Christian
The great number of copies is a strength. Scholars compare them to recover what the writers wrote. Most differences are spelling or word order that change nothing.
Most of the differences among the manuscripts are immaterial slips such as spelling and word order.
Rebuttal
Nobody says 400,000 differences mean 400,000 doctrines. But three passages are not slips: the verse on the Trinity, the end of Mark, and the story of the woman taken in adultery. The same hand-copying that made the small slips also carried doctrine into the text.
The Islamic perspective
The Bible's copies differ from each other more often than the New Testament has words. Some differences are whole passages carrying doctrine. The Qur'an, sent to the Prophet (ﷺ), was guarded by God (﷾) as He promised, and memorised and written down from the start.
Scholars estimate 200,000 to 400,000 differences among the New Testament manuscripts. That is more than the number of words in the New Testament.
The earliest copies lack three passages. They are the 'Father, Word and Spirit are one' verse, Mark's last twelve verses and the story of the adulteress.
The Hebrew Bible survives in several text forms that differ in thousands of places. Its oldest complete copy is medieval.
At 1 Samuel 13:1 the Hebrew has lost a number. The King James Version, the World English Bible and the JPS 1917 translation print three different verses.
The Qur'an states that God (﷾) Himself guards it from corruption. It offers its lack of discrepancy as a test of its origin.
The Qur'an was written down by the Prophet's (ﷺ) own scribes. Soon after his death it was gathered into one volume, from the writings and from those who knew it by heart.