Islam is the guidance of sharia law and governance there is no separation of "Law" "Islam" and "Governance" in the Moslem World.
The Shariʻah (literally "the path leading to the watering place") is Islamic law formed by traditional Islamic scholarship, which most Muslim groups adhere to. Shariʻah "constitutes a system of duties that are incumbent upon a Muslim by virtue of his or her religious belief
The Quran set the rights, the responsibilities and the rules for people and for societies to adhere to.
Mainstream Islamic law does not distinguish between "matters of church" and "matters of state"; the scholars function as both jurists and theologians. Currently no government conforms to Islamic economic jurisprudence, but steps have been taken to implement some of its tenets.
https://en.wikipedia.org/wiki/Islam