"Any one who, after accepting Faith in Allah, utters unbelief, EXCEPT UNDER COMPULSION, his heart remaining firm in faith -- but such as open their breast to unbelief, -- on them is Wrath from Allah, and theirs will be a dreadful Chastisement (Quran 16:106).â€ Taqqiya is an Islamic strategy where a mujahuddin deceives in order to fight for jihad. It is an integral part of Islamic philosophy. This technique was used by Muhammad in his several battles. In Hadiths it is said: (Verily) we smile for some people, while our hearts curse (those same people) Some sunnis claim that it actually is a shia technique. This interseting write up from a shia source tells how Al-Taqqiya is an integral part of quran,hadiths and sira. One should know this doctrine to understand the psychology of muslims. Al-Taqiyya, Dissimulation Part 1 | A Shi'ite Encyclopedia | Books on Islam and Muslims | Al-Islam.org Excerpts: "al-Taqiyya is with the tongue only; he who has been coerced into saying that which angers Allah (SWT), and his heart is comfortable (i.e., his TRUE faith has not been shaken.), then (saying that which he has been coerced to say) will not harm him (at all); (because) al- Taqiyya is with the tongue only, (not the heart)." "al-Taqiyya is the uttering of the tongue, while the heart is comfortable with faith." "It is permissible to speak words of unbelief when al-Taqiyya is mandatory."