Usul al-Din

Theology of Twelver Shias contains five principles of the Shia religion known as Uṣūl ad-Dīn (Arabic: أصول الدين عند الشيعة‎‎). Usul al-dín is an Arabic Islamic term which literally translates as 'foundation of the faith', roughly interpretable as 'theology'.

The Shia roots of religion are a set of theological beliefs, in contrast to the ten practices prescribed in the Shia ancillaries of the faith.

All books of Resalah start with an explicit disclaimer stating that no proof shall be given for any of the points in the Usul al-dín.

The Marja argue that it is permissible to imitate in matters of practical Islam, for example, how one is supposed to do Salat, without being familiar with evidence and arguments for the conclusions.

However, they argue that the matters in the roots of religion are much too important to be merely imitated, and it is the responsibility of each individual to make themselves personally familiar with the arguments and evidence for each article of faith.

There are five articles of faith in the Shia roots of religion.

Tawhid (Arabic: توحيد‎, translit. Tawḥīd‎, also spelled Tauhid or Tawheed) is the Islamic concept of monotheism. In Arabic, Tawḥīd means "unification, i.e. to unify or to keep something unified as one." In Islam, Tawḥīd means to assert the unity of God, it is not just unity of God Almighty but also Uniqueness, as defined in Quran surah 112, He is not born of anyone nor gave birth to any one, nor is any one like Him. The opposite of Tawḥīd is shirk, which means "Association" in Arabic. Muslims view polytheism and idolatry as shirk.

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