Much of the content of the Qur'an centers on the themes of faith in the One God and rejection of all other deities or objects of worship. Terms relating to belief, unbelief, hypocrisy, monotheism, and polytheism abound. In fact, the core message of the Qur'an relates to faith, so it is not surprising that numerous verses relate not only to Islam but also to other religious traditions.

While the Qur'an clearly rejects the idea that there are many gods, it does recognize that other prophets and traditions existed before Muhammad. In particular, it often refers to Christians and Jews, and, as we have already seen, confers on them the title People of the Book, thus recognizing the scriptures which Christians and Jews had received from God.

This recognition of Christians and Jews does not mean that the Quran is not critical of them. In fact, members of the Jewish tribes that opposed Muhammad in Medina are sometimes censured harshly. Similarly, the Qur'an condemns those Christians who claim that God is the third of three instead of recognizing only one God. When the Qur'an criticizes a Jewish, Christian, or even Muslim community, Muslim scholars have generally understood this as referring to the specific conduct of certain individuals or groups within the community. In some cases, this view is based on the traditional interpretation of a verse. In other cases, it is reflected in the specific wording of the Qur'anic verse; for example, Some Jews distort the meaning of [revealed] words: they say, “We hear and disobey" And: Those We gave Scripture know it as well as they know their sons, but some of them hide the truth that they know.

The Qur'an appears to be somewhat ambivalent towards the recipients of previous revelations, and some verses are difficult to reconcile with others. In order to understand these verses, we must read these passages in a highly nuanced way and with an understanding of their individual contexts.

At times the Qur'an appears harshly critical of the failure of older religious communities (such as the Jews and Christians) to accept the prophethood of Muhammad, and the new guidance given by God to Muhammad.

At other times, however, it clearly affirms the righteous among those of other faiths: For the [Muslim] believers, the Jews, the Sabians, and the Christians - those who believe in God and the Last Day and do good deeds - there is no fear: they will not grieve. Quran 5:69

Similarly, the Qur'an censures religious exclusionism, and also points to a higher, divinely ordained purpose in the diversity of human religions, as in the following verse:

We [God] have assigned a law and a path to each of you. If God had so willed, he would have made you one community, but He wanted to test you through that which He has given you, so race to do good: you will all return to God and He will make clear to you the matters you differed about. Quran 5:48

Excerpted from the book "The Qur'an by Abdullah Saeed."