أو الأسباب الموجبة له (Introduction to the constitution and the evidences that make it obligatory) published by Hizb ut-Tahrir 1382 Hijri (1963 CE). Please refer to the original Arabic for accurate meanings. Please note some of the adopted opinions of the Hizb have changed since the time the book was published so any of the adopted literature published after this book which contradicts what is mentioned in this book abrogates those specific points.
The Khalifah does not adopt any specific Shari'ah rule in matters related to rituals except in Zakat and Jihad, nor does he adopt any thought from among the thoughts related to the Islamic Aqeedah.
Explanation and evidences:
Evidence of this article is derived from the fact that the adoption is in itself Mubah for the Khalifah and not obligatory upon him. Just as he is entitled to adopt certain rules, he is also entitled to refrain from adopting certain rules. It is not matter which he imposes upon people, because it is not them who adopt, it is rather a matter that concerns him only; thus he is entitled to either adopt or to abstain from adopting. He is entitled to act according to what he deems fit. It emerged from the events of Al-Ma’mun, pertaining the Fitna (strife) of the creation of the Qur’an, that adoption in the thoughts related to Aqeedah matters has caused problems to the Khalifah and Fitna amongst the Muslims. It also emerged from the Fatimide’s adoption of Imam Ja’afar’s school of thought that this caused discontent amongst the followers of other schools of thought and a resentment towards this type of adoption, especially in the opinions related to Aqeedah matters and the opinions related to rituals. Therefore, the Khalifah deems it fit to abstain from adopting in matters related to Aqeedah and in rules related to rituals in order to avoid problems and in order to observe the consent and the tranquillity of the Muslims. Hence, the Khalifah chooses not to adopt in these two matters and Shari'ah has not made it an obligation upon him to adopt; thus he may choose not to adopt. Abstaining from adopting in matters of Aqeedah and in rituals does not mean that it is forbidden for the Khalifah to adopt in them, it rather means that the Khalifah chooses not adopt, for he can either adopt or abstain from adopting. Thus he may choose not to adopt. That is why the article stated that the Khalifah does not adopt rather than stating that the Khalifah is forbidden from adopting, which indicates that he may choose not to adopt.
This is as far as the evidence of the Article is concerned. As for choosing to abstain from adopting in Aqeedah matters and in rituals, this is based upon two issues: The hardship caused by coercing people to follow a specific opinion related to Aqeedah matters and the fact that what prompts the Khalifah to adopt is in fact the management of the Muslims’ affairs by one single opinion and the preserving of the unity of the State and the unity of the rule. Hence, he adopts in matters related to relationships between individuals and related to public matters and he does not adopt in matters related to relationship of man with his God.