is lying permitted?

that depends on you, really.

but let's see what islam says about it.

1. write up from a christian point of view

2. write up from a muslim point of view

the shi'ite principle of takeyya is the root of it. the following is an extract from investigateislam.com:
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The principle of Al-Takeyya

The Arabic word, "Takeyya", means "to prevent," or guard against. The principle of Al Takeyya conveys the understanding that Muslims are permitted to lie as a preventive measure against anticipated harm to one's self or fellow Muslims. This principle gives Muslims the liberty to lie under circumstances that they perceive as life threatening. They can even deny the faith, if they do not mean it in their hearts. Al-Takeyya is based on the following Quranic verse:

"Let not the believers Take for friends or helpers Unbelievers rather than believers: if any do that, in nothing will there be help from Allah: except by way of precaution (prevention), that ye may Guard yourselves from them (prevent them from harming you.) But Allah cautions you (To remember) Himself; for the final goal is to Allah." Surah 3: 28

According to this verse a Muslim can pretend to befriend infidels (in violation of the teachings of Islam) and display adherence with their unbelief to prevent them from harming him.

Under the concept of Takeyya and short of killing another human being, if under the threat of force, it is legitimate for Muslims to act contrary to their faith. The following actions are acceptable:

* Drink wine, abandon prayers, and skip fasting during Ramadan.
* Renounce belief in Allah.
* Kneel in homage to a deity other than Allah.
* Utter insincere oaths.