Islam allows Muslims to lie in 4 ways
Taqiyya - Lying about one's Muslim identity, i.e. denying being a Muslim or lying about Islam, e.g. that Islam is peaceful and tolerant. This is a Shiite term: the Sunni counterpart is Muda'rat.
It is the best known term, but by far not the only way in which Muslims deceive non-Muslims - with the full approval of Islamic scriptures:
Muruna - Blending in by setting aside some practices of Islam or Sharia in order to advance Islam; this may include drinking alcohol, eating pork or a Muslim woman marrying a non-Muslim man.
al-Tawreya - Intentionally creating a false impression by saying something that is technically true, when knowing that the listener will interpret it in a different way. This practice has a broader applications than Taqiyya.
Kitman - Lying by omission. An example would be when Muslim apologists quote only a fragment of verse 5:32 ("if anyone kills a human being it shall be as if he had killed all mankind") while failing to explain that under Islam, only Muslims are considered as "human beings", that this verse was a threat against Jews if they were to kill Muslims and failing to mention that the rest of the verse and the following verse mandate the murder of anyone who "spreads corruption and mischief", which typically means any attempt to criticize Islam, committing apostasy or preaching any other religion.
Taqiyya
A Muslim I just debated claimed that Muslims would never practice Muruna, as that would negate the whole point of being a Muslim, that a Muslim could not break Islamic rules. He also claimed that Muslims were only allowed to lie if their lives were in danger, so basically that Taqiyya only could be used to save their skin.
He was practicing Taqiyya as he was typing his lies đ
The only condition Islam puts on Muslims for the use of these methods of lying to non-Muslims is that their lies must advance the cause of Islam.
Resouces
Taqiyya:
- https://www.thereligionofpeace.com/pages/quran/taqiyya.aspx
- https://en.wikipedia.org/wiki/Taqiya
- https://paulsutliff.blogspot.com/2015/03/taqiyya-art-of-lying-in-islam.html
Tawriya:
- Islamic Doctrine Permits âCreative Lyingâ
https://www.raymondibrahim.com/2012/02/28/tawriya-lying/
Muruna
Summary as a Meme
Short version
Long version