Does Christianity claim that the Bible is God's only Word?

I'm going to write a separate answer for what I believe is a separate question. You ask if the Bible is the ONLY word of God. Most Christians would say 'absolutely yes', but the actual position is a little more complex than that. It is certainly true that mainstream Christianity has never acknowledged any additional scriptures, and most consider that the Bible is a 'closed canon', which means that no scriptures can be added to it. However the 'canon' is only the acknowledged and approved list of God's writings. Could God cause to be written some other book for some reason? Yes he could. However he would not create a book that contained things necessary for salvation; i.e. it might contain useful teachings, but not things that a Christian had to accept in order to be a true Christian.

It is important to note that Christianity does not consider itself a wholly and entirely different religion from Judaism. Instead Christian belief is that God worked his will through his Chosen People, the Jews, promising them a Saviour (Messiah) in due course. However when that Saviour was sent, some accepted him and some did not. Those that did became Christians, and those that did not continued to call themselves Jews.

Up until the time of Jesus, God acted through the Jews. This included revealing himself to them, and causing to be written holy books of prophecy, teaching and history - the Jewish scriptures. Christians consider those writings to be just as much written by God as anything written in the time of Jesus. The teachings of Jesus do override the Jewish scriptures, because God made a new revelation through him - however they are still considered holy writings, as they reveal God's will for his people at the time they were written.

The Christian Bible therefore contains two parts - the Jewish scriptures are referred to as the Old Testament (more accurately Old Convenant) and the writings about Jesus are the New Testament (New Covenant).

Lots of good and interesting answers here, but one Catholic perspective is missing.

Bl. Pope John Paul II's Theology of the Body made it clear that God one way God speaks through us is through His creation. To be sure, Creation itself, is in the Bible, but the Bible doesn't say. "Men shall be X because I, the LORD your God created them this way and woman shall be X because I, the LORD your God created them that way". It does say "Men shall DO this and women shall DO that", but doesn't go into the inherent qualities of the sexes.

The Torah is part of the Bible: it is the first five books so is considered by Christians to be "the word of God".

Regarding the Bible being the word of God first, a verse regular quoted by Christians is 2 Timothy 3:16:

All Scripture is God-breathed and is useful for teaching, rebuking, correcting and training in righteousness.

Regarding the Bible being complete (i.e. no written* "words of God" following), Revelation 22:18-19 is often quoted:

I warn everyone who hears the words of the prophecy of this scroll: If anyone adds anything to them, God will add to that person the plagues described in this scroll. And if anyone takes words away from this scroll of prophecy, God will take away from that person any share in the tree of life and in the Holy City, which are described in this scroll.

(although some dispute this and say it is only referring to the last book of the Bible, Revelation itself).

_{*Some Christian (eg Pentacostal) churches practice "words of knowledge" which are "oral" words of God. It is a whole different topic, but Pentacostals would not accept them as valid if they contradicted Scripture.}

The Word of God Cannot Be Changed

When Christians use the word Bible, they are not merely referring to the New Testament, but to the Old Testament as well. This includes the Torah.

As the Quran (as well as the Bible) affirms, God's Word cannot be changed.

Perfect are the words of thy Lord in truthfulness and justice; no man can change His words; He is the All-hearing, the All-knowing. S. 6:115 Arberry

for them is good tidings in the present life and in the world to come. There is no changing the words of God; that is the mighty triumph. S. 10:64 Arberry

Recite what has been revealed to thee of the Book of thy Lord; no man can change His words. Apart from Him, thou wilt find no refuge. S. 18:27 Arberry

The grass withers, the flower fades, but the word of our God will stand forever. Isaiah 40:8 ESV

For truly, I say to you, until heaven and earth pass away, not an iota, not a dot, will pass from the Law until all is accomplished. Matthew 5:18 ESV

So, because we know God's Word cannot be changed, we know that we can have confidence in the accuracy and reliability of the Old and New Testaments.

Warnings from God's Word

Using, then, the Old and New Testament as a foundation, there are a few key points with regard to any new work that proclaims itself the Word of God.

• God's Word warns that there are many deceivers who will attempt to distort the truth about God.

  For many deceivers have gone out into the world, those who do not confess the coming of Jesus Christ in the flesh. Such a one is the deceiver and the antichrist. 2 John 1:7 ESV

• God's Word warns against the preaching of any other gospel other than the gospel of Jesus Christ. In fact, it goes so far to say that even if an angel of God should preach a different gospel, we are to reject it.

  I am astonished that you are so quickly deserting him who called you in the grace of Christ and are turning to a different gospel— 7 not that there is another one, but there are some who trouble you and want to distort the gospel of Christ. 8 But even if we or an angel from heaven should preach to you a gospel contrary to the one we preached to you, let him be accursed. 9 As we have said before, so now I say again: If anyone is preaching to you a gospel contrary to the one you received, let him be accursed. Galatians 1:6-9 ESV

The Quran's Affirmation of the Bible

The Quran itself affirms the Old and New Testaments:

Dispute not with the People of the Book save in the fairer manner, except for those of them that do wrong; and say, 'We believe in what has been sent down to us, and what has been sent down to you; our God and your God is One, and to Him we have surrendered.' S. 29:46 Arberry

Then We gave Moses the Book, complete for him who does good, and distinguishing every thing, and as a guidance and a mercy; haply they would believe in the encounter with their Lord. This is a Book We have sent down, blessed; so follow it, and be godfearing; haply so you will find mercy; lest you should say, 'The Book was sent down only upon two parties before us, and we have indeed been heedless of their study'; or lest you say, 'If the Book had been sent down upon us, we had surely been more rightly guided than they.' Yet indeed a clear sign has come to you from your Lord, and a guidance and a mercy; and who does greater evil than he who cries lies to God's signs, and turns away from them? We shall surely recompense those who turn away from Our signs with an evil chastis*m*nt for their turning away. S. 6:154-157 Arberry

Conclusion

So, whenever any other book is offered as another Word from God, we need to be very careful and "test the spirits to see whether they are from God, for many false prophets have gone out into the world." (1 John 4:1 ESV) Also, if any other book contradicts the Bible, then it is another gospel and must be rejected.

In the case of the Quran, it was actually claimed to be delivered to Muhammad by an angel of God. God's Word gives us a very specific warning about such a claim. The Quran contradicts the Bible and presents another gospel.

The Bible is God's Word--and God's Word cannot be changed. Therefore, we must conclude that the Quran is not the Word of God, and that is why Christians do not accept it as such.

From the context and questions, the real question here seems to be:

Does Christianity permit additional works, such as the Qu'ran (in particular), to be the word of God

Well, firstly, the Bible is not usually taken to be the word of God; it is written by humans, with the emphasis that those words were supposedly inspired and steered by God.

As for "does Christianity allow the Qu'ran as authentic": no, it does not, frankly. By simple logic: if a Christian believed the Qu'ran to be the true and authentic word of God, then they would need to follow those beliefs / instructions, which would mean: they were following Islam. This is clearly not the case; it could even be argued that the similarities between the practices of Christianity and Islam are at best superficial.

So: no.

The assumption that you make is that the Bible is "Jesus' book." It may or may not be the "Injil." In fact, Jesus neither wrote nor actually authored any piece of the book. Indeed, unlike Muhammed, Jesus did not even receive the Word, but rather was the Word of God. As John 1 tells us:

1 In the beginning was the Word, and the Word was with God, and the Word was God. 2 He was with God in the beginning. 3 Through him all things were made; without him nothing was made that has been made. 4 In him was life, and that life was the light of all mankind. ... 14 The Word became flesh and made his dwelling among us. We have seen his glory, the glory of the one and only Son, who came from the Father, full of grace and truth.

This is picked up in Hebrews, where the author states:

1 In the past God spoke to our ancestors through the prophets at many times and in various ways, 2 but in these last days he has spoken to us by his Son, whom he appointed heir of all things, and through whom also he made the universe.

Indeed, while the Bible is our perfect guide to the nature of God, it is to be understood that the Word points us to God because God is holy.

That Jesus is the exclusive way of salvation is made clear by Jesus' first disciples, Peter and John. When the Jewish High Priest brought them up on charges, they said of Jesus:

Salvation is found in no one else, for there is no other name under heaven given to mankind by which we must be saved. (Acts 4:12)

Furthermore, Jesus himself was clear that he was the exclusive one and only Word, saying in John 14:6:

Jesus answered, "I am the Way and the Truth and the Life. No one comes to the Father except through me.

The fundamental distinction I am making is this - Christians do not believe Jesus to be a prophet or a teacher. Christians believe him to be God. As God, he was "the Word" (a Greek term Logos that brings the fundamental idea of being the one through whom all things are created and given meaning.) Muhammed did not claim to be God. Jesus did. The exclusivity of the "Bible" as God's Word doesn't make sense, because Jesus is the point, not the book. Unlike Islam, we do not restrict our understanding of God's Word to a single language, nor do we venerate the Scriptures as Islam does. Instead, we believe that God is "the Word" and that Jesus is God, not a prophet

The Bible (and I say this as one who has an exceedingly high view of the authority of Scripture!) is not the "ONLY" word of God, because Jesus is the Word. Any would-be Scripture that denies this fundamental tenet of who Jesus is, is by definition, not a Christian Scripture. Jesus, being the fundamental Word, is the only test.

Unlike a prophet who merely is God's servant, as Christians, we make the audacious claim that God became flesh, dwelt among us, loved us, and saved us. Jesus is not a messenger, but God.