The people of  “the book”  are christians and jews who follow THE BIBLE. Muslims usually claim that the Bible is corrupted but that doesn’t fit the bill. The Bible was a complete book for many centuries before Muhammed even entered the scene, and he seems to trust it as a complete book.

“If you (Muhammad) are in doubt regarding that which We have revealed to thee, ASK those who READ the book from before you…” S. 10:94

If the Bible is corrupted or lost, this proves that Allah is telling Muhammad to verify his own message, the Quran, on a corrupted source! Therefore by disproving the Bible you would also disprove the Quran.  Even the Quran says to judge based on previous scriptures.

“And I will write down (my mercy) for those who are righteous and give alms and who believe in our signs; who follow the apostle, the unlettered prophet, whom they find written in the Torah and the Gospel that IS WITH THEM.”

Here the Quran even claims that Muhammad is found in previous scriptures! So if the Bible was corrupted then we must conclude that Allah is a liar since we wouldn’t be able to find Muhammad in it.  If it is corrupted then it shows that Muhammad is a corrupted prophet being prophesied by a corrupted book.

“And let the People of the Gospel JUDGE by what God has revealed in it. If any fail to judge by what God has revealed, they are licentious.” S. 5:50 “

“If only the People of the Book had believed and been righteous, we should have blotted out their sins and admitted them to gardens of bliss.” “If only they had performed the Torah and the Gospel and all that was revealed to them from their Lord, they would have eaten from above and from under their feet. Among them is a People (umma) on the right course, but evil is that which many of them do…”

“Say,O People of the Book! You are not (founded) on anything until you PERFORM the Torah and the Gospel, and what was revealed to you from your Lord.” S. 5:68-71

Hence to accept Bible corruption, one would be force to conclude that Allah’s revelations can be change by mere human beings.  Also it says that the people of the book (Bible means book) have to perform the Torah.

The words of thy Lord are perfect in truth and in justice; NONE CAN CHANGE HIS WORDS: For He is the one who heareth and knoweth all. S. 6:115

THERE IS NONE THAT CAN ALTER THE WORDS OF ALLAH. Already hast thou received some account of those messengers. S. 6:34

THERE IS NO CHANGING THE WORDS OF GOD; that is the supreme triumph. S. 10:65

And recite that which hath been revealed unto thee of the Scripture of thy Lord. THERE IS NONE WHO CAN CHANGE HIS WORDS, and thou wilt find no refuge beside Him. S.18:27

If the Bible is corrupted or lost then this means that the Quran is incorrect.

“God has bought from the believers their selves and their wealth, and for them is the garden (of Paradise) if they fight in the ways of God: and whether they kill or are killed, the promise of God IS true in the Torah and the Gospel and the Qur’an, and who is more faithful to his promise than God?” S. 9:111

“To you (Muhammad) We revealed the book in truth,attesting to (the truth of) that which IS between his (its) hands from the scripture (the Torah and Gospel), and guarding it (wa muhaiminan `alaihi)…” S. 5:51

According to the Quran, the promise of God is true in both the Torah and Gospel. Also Allah said that he revealed “THE BOOK”.

“They (the Meccans) say, `Why does he not bring us a sign from his Lord?’ What! Has not a clear sign come to them in what IS in the former pages (al-suhuf al-aulla )?” S. 20:133

“And before thee (Muhammad), We sent no one, except men, to whom We granted revelation. ASK (plural) the people of the Scripture message, if you don’t know.” S. 21:7

According to the Quran clear proof of God himself is in the former scriptures of the Torah and Gospel and he even commanded Muhammad to ask the people of the scripture if he didn’t know.

Mohammed said, “Whoever changes his Islamic religion, kill him.” (Hadith Al Buhkari vol. 9:57)

“Slay the idolators [non-Muslims] wherever ye find them, and take them captive, and besiege them, and prepare for them each ambush. Fight against such of those who have been given the Scripture as believe not in Allah nor the last Day…. Go forth, light-armed and heavy-armed, and strive with your wealth and your lives in the way of Allah! (Sura 9:5,29,41).

So according to the Quran self defence is not a needed excuse for slaying someone else, but it’s enough if he or she is a non-muslim.

Also read “How to explain the trinity for muslims”.