It is frequently claimed that the fatwa of Ibn Taymiyyah regarding the Mongols’ disbelief because of their book “al-Yasiq” applies to any Muslim government that implements laws derived from any sources other than the Qur’an and Sunnah.
This is a mistake for more than one reason. Firstly, because the kufr of the Mongols is due to the fact that they believed “al-Yasiq” was revealed by Allah, as explained by Ibn Kathir. Secondly, because it is inevitable that any government will necessarily have to implement some laws that are not explicitly defined by the Qur’an and Sunnah, and we have too many examples of this from the Khulafah Rashideen than we can list.
What we have to ask is, “is the Shari’ah the supreme source of legislation for the government or not? Are the permanent, unchanging, explicit rulings of the Qur’an and Sunnah enforced? And whatever is lacking in terms of the implementation of these explicit rulings, are these lapses sufficient to nullify the Islamic character of the government legally? Are there legitimate excuses, is the government subject to coercion, are there circumstances that the government believes make it impossible to correct those lapses at the present time, and so on?”