"Sharia is believed by Muslims to be the divinely ordained legal system of Islam. It governs every aspect of life: politics, economics, hygiene, marriage and family relationships, diet, warfare, crime. Everything is covered."
There are four Sunni schools of Islamic law. I am currently reading an English translation of one of those schools. The book is
Reliance of the Traveller by noted Islamic scholar Ahmed ibn Naqib al-Misri (translated by Nuh Ha Mim Keller and published in 1999).
In the introduction, the author states, "The four Sunni schools of Islamic law, Hanafi, Maliki, Shafi'i, and Hanbali, are identical in approximately 75 percent of their conclusions. ... The present volume [The Reliance of the Traveller] represents one of the finest and most reliable short works in Shafi'i jurisprudence."
"Just a few pages before this (pages 595-596), the Islamic law code says this about freedom of religion:
Leaving Islam is the ugliest form of unbelief (kufr) and the worst. It may come about through sarcasm, as when someone is told, "Trim your nails, it is sunna," and he replies, "I would not do it even if it were," as opposed to when some circumstance exists which exonerates him of having committed apostasy, such as when his tongue runs away with him, or when he is quoting someone, or says it out of fear.
When a person who has reached puberty and is sane voluntarily apostasizes from Islam, he deserves to be killed.
In such a case, it is obligatory for the caliph (or his representative) to ask him to repent and return to Islam. If he does, it is accepted from him, but if he refuses, he is immediately killed.
What other acts of faith (or non-faith) would invite capital punishment under Sharia? Here are just a few more (pages 596-597):
to speak words that imply unbelief such as 'Allah is the third of three,' or 'I am Allah'-- unless one's tongue has run away with one, or one is quoting another, or is one of the friends of Allah Most High in a spiritually intoxicated state of total oblivion ...
to revile Allah or His messenger ...
to deny the existence of Allah, His beginingless eternality, His endless eternality, or to deny any of His attributes which the consensus of Muslims ascribe to Him;
to be sarcastic about Allah's name, His command, His interdiction, His promise, or His threat;
to deny any verse of the Koran or anything which by scholarly consensus belongs to it, or to add a verse that does not belong to it ...
for a tyrant, after an oppressed person says, 'This is through the decree of Allah,' to reply, 'I act without the decree of Allah' ...
to revile the religion of Islam;
to deny the existence of angels or jinn or the heavens;
to be sarcastic about any ruling of the Sacred Law;
or to deny that Allah intended the Prophet's message ... to be the religion followed by the entire world. There are others, for the subject is nearly limitless.
While there are "secular" Muslims who believe that Sharia for the most part should not be binding on society, apparently many millions of Muslims seriously believe that this is the law that must be imposed upon all people everywhere all the time."
https://pjmedia.com/faith/2016/06/10/what-exactly-is-sharia-law-and-what-does-it-command/3/
