Another attempt by Sunnis is to create a way to seperate between the scriptures and thus create a society where Jews have their own laws and Christians have their own laws etc. This of course makes it easy for them. For this to succeed two things are needed, abrogation of the previous scriptures and apostasy laws to prevent people from flipping from one side to another making it easier for them. Then a Jews can flip to Islam whenever its convenient for him and then flip back when the need is not there. To create a theocracy they need to make religion as an identity that can be established from birth. So Muslims go to Islamic courts and Jews to Judaic courts and so on. When there is dispute, the Islamic court takes dominion. This system continues to this day and is one of the reason why recent fatwas in Egypt forbids a Christian wife from inheriting her Muslim husband. The verses they quote are
O Messenger. let not those grieve thee, who race each other into unbelief (whether it be) among those who say "We believe" with their lips but whose hearts have no faith; or it be among the Jews,- men who will listen to any lie,- will listen even to others who have never so much as come to thee. They change the words from their (right) times and places they say, "If ye are given this, take it, but if not, beware!" If any one's trial is intended by Allah, thou hast no authority in the least for him against Allah. For such - it is not Allah.s will to purify their hearts. For them there is disgrace in this world, and in the Hereafter a heavy punishment.
5.42. (They are fond of) listening to falsehood, of devouring anything forbidden. If they do come to thee, either judge between them, or decline to interfere. If thou decline, they cannot hurt thee in the least. If thou judge, judge in equity between them. For Allah loveth those who judge in equity.
43.But why do they come to thee for decision, when they have (their own) law before them?- therein is the (plain) command of Allah. yet even after that, they would turn away. For they are not (really) People of Faith.
It was We who revealed the law (to Moses) therein was guidance and light. By its standard have been judged the Jews, by the prophets who bowed (as in Islam) to Allah.s will, by the rabbis and the doctors of law for to them was entrusted the protection of Allah.s book, and they were witnesses thereto therefore fear not men, but fear me, and sell not my signs for a miserable price. If any do fail to judge by (the light of) what Allah hath revealed, they are (no better than) Unbelievers.
We ordained therein for them "Life for life, eye for eye, nose or nose, ear for ear, tooth for tooth, and wounds equal for equal." But if any one remits the retaliation by way of charity, it is an act of atonement for himself. And if any fail to judge by (the light of) what Allah hath revealed, they are (No better than) wrong-doers.
And in their footsteps We sent Jesus the son of Mary, confirming the Law that had come before him We sent him the Gospel therein was guidance and light, and confirmation of the Law that had come before him a guidance and an admonition to those who fear Allah.
Let the people of the Gospel judge by what Allah hath revealed therein. If any do fail to judge by (the light of) what Allah hath revealed, they are (no better than) those who rebel.
To thee We sent the Scripture in truth, confirming the scripture that came before it, and guarding it in safety so judge between them by what Allah hath revealed, and follow not their vain desires, diverging from the Truth that hath come to thee. To each among you have we prescribed a law and an open way. If Allah had so willed, He would have made you a single people, but (His plan is) to test you in what He hath given you so strive as in a race in all virtues. The goal of you all is to Allah. it is He that will show you the truth of the matters in which ye dispute;
And this (He commands)Judge thou between them by what Allah hath revealed, and follow not their vain desires, but beware of them lest they beguile thee from any of that (teaching) which Allah hath sent down to thee. And if they turn away, be assured that for some of their crime it is Allah.s purpose to punish them. And truly most men are rebellious.
Do they then seek after a judgment of (the days of) ignorance? But who, for a people whose faith is assured, can give better judgment than Allah.
Here they say Jews rule under Jewish law and Christians rule under Christian law and.....wait a minute what Christian laws are they talking about? They are none according to them. This is why the apostasy hadith used a Jew and not a Christian. It all begins to take shape. The reality the Koran says we should follow these scriptures since each confirms the other while they say each to his own. The hadith they bring up is this
Hadith - Sahih Bukhari 6.79, Narrated by Abdullah ibn Umar
The Jews brought to the Prophet a man and a woman from among them who had committed illegal sexual intercourse. The Prophet said to them, "How do you usually punish the one amongst you who has committed illegal sexual intercourse?" They replied, "We blacken their faces with coal and beat them." He said, "Don't you find the order of Ar-Rajm (i.e. stoning to death) in the Torah?" They replied, "We do not find anything in it." 'Abdullah bin Salam (after hearing this conversation) said to them, "You have told a lie! Bring here the Torah and recite it if you are truthful." (So the Jews brought the Torah). And the religious teacher who was teaching it to them, put his hand over the Verse of Ar-Rajm and started reading what was written above and below the place hidden with his hand, but he did not read the Verse of Ar-Rajm. 'Abdullah bin Salam removed his (i.e. the teacher's) hand from the Verse of Ar-Rajm and said, "What is this?" So when the Jews saw that Verse, they said, "This is the Verse of Ar-Rajm." So the Prophet ordered the two adulterers to be stoned to death, and they were stoned to death near the place where biers used to be placed near the Mosque. I saw her companion (i.e. the adulterer) bowing over her so as to protect her from the stones.
Obviously they couldn't say the same with a Christian since Jesus never had a community he had a political dominion over and there was no need for him to settle dispute. This way they can solve the theocracy problem of what to do with non Muslims. And then to solve the problem of someone flipping they brought the hadith of apostasy. This makes it easy for them to categorize people and keep them in that categorization. This explains the fatwa issued against the two writers in Saudi arabia who said Jews and Christians are not necessarily infidels. The Sheikh said "this means that a person can change from a Muslim to a Christian", another words he can flip thus making their theocracy untenable. Thats the reason why they insist that jews and Christians are infidels because they fear people will flip from one identity to another making ruling according to religious law impossible. Thus to need to threaten Muslims with execution if they flip. The Koran however never seperated between the scriptures and thus they needed to nullify the authority of the previous scriptures with the lie that the previous scriptures are corrupted.
So how would you create a seperate Islamic identity for people? You create rituals that identify them from others like the Jews did. You then bring about an oral tradition that defines their life and society just like the Jews did. You then create a state legal framework that seperates these identities. But if these were religious laws why do they change and why do they get abrogated? To solve this they invoked the prophetic authority. Its not that God's laws change but that each prophets come with a new "Islam". So if the Koran gives different rulings regarding an issue they solve that by abrogation. Not only that each prophet abrogates another but the prophet themselves abrogate their earlier "law" due to circumstances like Mecca and Medina etc. But this abrogation must only take place during their lifetime and nobody elses. And if the scriptures give variant rulings regarding an issue they solve that once again by abrogation. Like a balance sheet statement in accounting they want a point of time. That point in time is the day before the prophet passed away.
Abrogation and apostasy is the foundation and the oral traditions are the ammunition. This is why they need a prophetic sunnah because it can be abrogated every time a prophet comes with a new sira(biography and tradition) but God's sunnah as the Koran says does not change or get substituted. The reality the real difference is that HUMAN laws change while God's law does not. And God does not squeeze laws between prophet's biograpies. To say that God will change "laws" in Mecca and Medina to fit the prophet's circumstances is placing God under the prophet and not vice versa. This is why the Koran gives variances because human circumstances change. So if you ask them well if things change during the prophet's time then why can't it cahnge after that they will say because only a new prophet can bring a new law. This explains their fear of denying the finality of prophethood of Muhammad because they fear that a new religious figure can change their theocracy. By creating rituals they can say without hadiths then we can not practice these rituals when they really mean without hadiths there is no shariah and without shariah there are no clerics. The rituals are then used to justify another scripture they deduce legal judgement from. This explains why Bukhari's chapters are very different from the chapter headings of the Koran.
Those people who call themselves Koranist but refuse to accept the authority of the previous scriptures are the Sunni/Shia clerics best friends. Without abrogation the clerics are out of business.