If you are a Muslim, the Third and Fourth Centuries

There were many scholarly authorities during the the third century. Among them was Origen. He was born in Egypt in AD 184 and died in AD 253. He was renown for his godliness, so much so that pagan philosophers gave him their writings to edit and embellish. He was a Bible commentator and preacher. Dionysius, Bishop[ of Alexandria, and Gregory, Bishop of Neo-Caesarea, were men of similar distinction.
In the fourth century, we find the historian Eusebius of Caesarea who died in AD 340. Hilarius, who died in AD 366, also wrote during this time.
Some 50 works out of a total of nearly 100, from the pens of these eminent scholars, have come down to us. Some are interpretations of the Bible, while others a variety of subjects and are well-supported by quotes from most of the sacred writings. These authors lived at different times and in various places. Clement was famous in Rome, Ignatius in Antioch, Polycarp in Smyra, Justin Matyr in Syria, Irenaeus in France, Athenagorus in Athens, Theophilus in Antioch, Clement and Origen in Egypt, Tertullian in Carthage and Augustine in Hippo (both in North Africa), and Eusebius in Caesarea. This wide variety of writters indicates the spread of the Christian faith. There could have been no conspiracy among the Christians over such a vast area to corrupt their Scriptures. Christian scholars compared 686 copies of the New Testament with existing translations, excerpts and quotations and all were found to be uniform. This proves the freedom of the Bible from tampering, corruption, alteration, additions or omissions. It has been of unanimous persuasion among Believers that the integrity of the New Testament books has been preserved.
I will throw my Muslim friend a common objection that you will most likely say to me.

Objection:     
Scholars have disagreed over the chronology of the accounts of the Gospel of Christ because the ancients had shaky records upon which they based their writings. Those who followed passed on the doubtful texts. This resulted in disputes over when the various accounts of the Gospel were written.

Response:
The fact that we cannot accurately determine the dates when the Gospel accounts were written does not devalue them. The same is true of the Koran; although it is of more recent age than the Bible, Muslims have differed widely about the dates when the suras were composed. The location where certain suras were recited has been questioned. It is obvious that the Meccan suras descended before the Hijra and the Medinan suras came after. But whether the Prophet Muhammad recited a certain sura un Mecca or Medina, during a year of conquest, the farewell pilgrimage or one of his journeys cannot be proven. There have also been difference over the Fatiha ("the prologue"). Some have said it describes in Mecca but others say it was in Medina: still others have said it described in both cities ot that half came down in each. One opinion saus that Satan cried when the Fatiha descended. Some suras over which there are difference of opinion are the following: Jonah, Thunder, Pilgrimage, Salvation, Ya Sin, Sad, Apartments, The Merciful Lio, The Ranks, Congregation, Mutual Fraud,  The Kingdom, Mankind, Stinters, The Most High, Dawn, The Land, Night, Power.

This is the case with the Koran even though its date of composition is later than that of the Bible. There are also disagreement over of all parts of the Koran's contents- indeed within the very verses themselves. However, when the New Testament books were being collected, the only difference that arose concerned the entire collection of books, not the individual chapters and verses. But even with these discrepancies over the Koran, no one has devalued or rejected it.

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