When it comes to ethics and morality, most people would rank truthfulness very high among the values they would like to aspire to. Islam's relationship with truth and truthfulness is rather complex but we can, at the very least, say that Muslims are not required to tell the truth under all circumstances and that deceit is sometimes actively encouraged.
This is the case because Muhammad advocated a system of ethics where the guiding question is: ‘What will be good for Islam in these circumstances?’ The guiding question is, therefore, not ‘What is true’? Because of this it is perfectly permissible to tell lies and half-truths, especially if they are told to non-Muslims, if this can serve the interests of Islam.
The principle of using deception to further Islamic interests is very firmly established in the Qur’an. The following texts form the basis for the doctrine of taqiyya (dissimulation or deception) as an acceptable part of Islamic morality: