The Qur'an's statement is the constitution.

Question:
Their saying, "The Qur'an is the constitution"; what is the ruling on this phrase? And what is a constitution?

Answer:
Answer: Yes, there is nothing wrong with the phrase. A constitution means the methodology that a state follows, and the people follow it in that regard. The Qur'an is our methodology that we follow; we make lawful what it makes lawful and forbid what it forbids, we act according to its clear verses and believe in its ambiguous ones, and we do not deviate from it to the right or to the left. We do not import systems from the disbelievers and from humans who have no knowledge and who do not follow a Book or a methodology, but rather follow their desires and what their misguidance and tyrants legislate for them, or what those who do not believe in the Hereafter legislate for them in the form of systems and man-made laws. The servants have a methodology that Allah has legislated, and they must follow it and deal according to it; they are not to be negligent.