This common misconception started with Goldziher. Goldziher, who was an Orientalist, poorly defined ‘taqiya’ and presented it as some sort of training in deception. Nothing is further from the truth. Almost all Muslim scholars_ whether Shiah or Sunni_ agree that although it is a grave sin to lie, it is permissible for a Muslim to conceal or even renounce his or her faith before an enemy in order to protect one’s life and honor.
This theological view came about as a result of an actual event. During the time of Prophet Muhammad, a Muslim named Amar bin Yassir was caught by Arab pagans and was tortured until he renounced his faith and condemned Prophet Muhammad (s.a.w). Once released, he came crying and confessed to the Prophet what he had done who asked him what he had felt in his heart at that time. He replied that he was fully content with his faith. The Prophet told him that if he was ever put in that position again, he can again do the same! Soon afterwards, God confirmed this by revealing the following verse: “Anyone 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 Penalty.” And thereafter, this very practical principle was established that it is more important to save one’s life and honor, without losing one’s faith, than to become a victim of evil.
People such as Goldziher got confused by certain statements by Imam Jafar Sadiq that ‘taqiya’ is obligatory and one who does not have ‘taqiya’ has no faith. These statements were made when Shiahs were being persecuted by the Abbasids and were in great danger of losing their lives. Revealing faith was a matter of life and death. And most Shiah scholars would tell you that ‘taqiya’ is only permitted in times of fear.
The only other time that a Muslim may use deception is on a battlefield to save lives or to gain the upper hand, but how is this any different than Mr. Rumsfeld statement that the Pentagon will use “strategic or tactical deception” during its war in Afghanistan?