One of the doctrines that Muslims have inherited from their tradition is that the Christians have falsified the Holy Scriptures. Supposedly this alteration occurred before the rise of Islam. In fact, Muslims are not aware of any writings in the Old Testament other than the Torah of Moses and the Zaboor (Psalms) of David. They are surprised to discover four Gospels in the New Testament, the Acts of the Apostles, as well as several Letters, and a book called the Vision or Apocalypse of John. They are surprised to discover that the Bible is a collection of 66 books. Therefore, it is very important for the Christian missionary to explain, in a loving and patient way, that the Word of God consists of the 39 books of the Old Testament and the 27 books of the New Testament.
It is better to approach the divisions of the Old Testament in a different way than we do in our English Bibles. I prefer the Hebrew division: Moses, the Prophets, and the Psalms. Moses refers to the Pentateuch, which the Muslims know as the Tawrat. The Prophets include Joshua, Judges, I and II Samuel, I and II Kings, Isaiah, Jeremiah, Ezekiel, Hosea, Joel, Amos, Obadiah, Jonah, Micah, Nahum, Habakkuk, Zephaniah, Haggai, Zechariah and Malachi. The third part of the Old Testament is known as the Writings. Here we find the following books: Psalms, Proverbs, Job, Song of Songs, Ruth, Lamentations, Ecclesiastes, Esther, Daniel, Ezra, Nehemiah, I and II Chronicles. Since the Book of Psalms was placed at the head of the third division of the Old Testament, quite often this section is known as The Psalms.
When we come to the New Testament, it is of great importance that we insist that we have one Gospel, i.e., one Injeel, and that its primary meaning is good news. It is definitely not a book that Jesus received from heaven as Muslims are taught in their tradition. The Word of God, as far as its contents are concerned, is both law and gospel. The Arabic word shari’a (law) is an important one to learn. God’s commands and promises are found in all of Scripture. The good news of Jesus is not to be confined to Matthew, Mark, Luke and John.
It is unfortunate that we often add to the Muslim’s misunderstanding of the Christian faith by talking about the Gospels as being of Matthew, or of Mark, or of Luke or of John. For example, in the Arabic translation the title is rendered “Injeel Matta.” This gives the impression that the subject matter of each gospel is its author, rather than Jesus Christ. Rather, we should be faithful to the original Greek word “kata,” which means, "according to” We must not give the impression that we have four gospels. There is only one gospel, one Injeel, and it is the good news of the Lord Jesus Christ.
There are some genuine offenses that we cannot avoid, such as the doctrines of the Trinity, the deity of Jesus Christ, as well as the historicity of the crucifixion. But we should not, inadvertently add more offenses or show lack of sensitivity, when we present the claims of the Lord Jesus Christ to a Muslim. Thus, we must emphasize, time and again, that we have only one gospel and that it is found throughout the entire Bible. For example, the book of Romans may rightly be called The Gospel according to Paul. It is the most thorough and systematic New Testament book that expounds the true nature of the gospel. There is good reason for starting our study of The Bible and Islam with this book, which was originally a letter that the apostle sent to the church in the very heart of the Roman Empire.