The sentence of those who judge by which Allah has not revealed
Allah (swt) said, -meaning- {And if any do fail to judge by (the light of ) what Allah has revealed, they are (no better than) Unbelievers}.
Allah has stated and decided in this Verse (sign) that the judge by which He has not revealed is disbelief. Sometimes, it is a major disbelief that excludes his perpetrator from Islam, and sometimes it is considered a minor one whose perpetrator is not excluded from Islam. This depends upon the case of the person.
The person who thinks that the judge by the Revelation of Allah is not necessary or believes that he has the choice whether to judge by it or not, or thinks that other rules and principles are better than Allah’s, or thinks that it is not applicable in our time, or aimed by its omission the satisfaction of disbelievers, then he certainly commits a major disbelief by that.
However, if he believes that the judgement by Allah’s Revelation is inevitable but he left it out knowing that he deserves punishment, then he is a disobedient and this is called a minor disbelief. Whereas, if he did not know about the judge of Allah in a certain case and he tried his best to reach a decision and made a mistake then he has striven but failed and his mistake is forgiven.
This is due to the personal judgements, whereas the case is different in the public judgements. Ibn Taimiah said, “ so if the ruler investigated the right judgement but he judged without knowledge, then he deserves Hell Fire. And if he is scholar and he judged by what contradicts with his knowledge, then he also deserves Hell Fire. And if he judged without just or knowledge, then he is worthier being in the Hell Fire. This is due to the judgement concerning personal quarrels.
As for he judged in a public case and he converted the Right into wrong and the wrong into right, and considered the Sunnah as a bid’a and the bid’a as a Sunnah, and prohibited what Allah and His Messenger have allowed, then allowed what they have prohibited, then this another case whose judgement should be left to the Lord of the ‘Alamin (All Creation). He is the ILah (God ) of the Messengers and the Only Owner of the Day of Recompence Whom He deserves the whole Praise in this world and in the Thereafter.
-meaning- {To Him belongs the Command, and to Him will you (all) be brought back}.
-meaning- {It is He Who has sent His Messenger (Muhammad (saw) with Guidance and the Religion of Truth, to proclaim it over all religion: and enough is Allah for a Witness}.
And he -Ibn Taimiah- said also, “no doubt that whosoever believes not in the necessity of judgement by what Allah has revealed is a disbeliever. Therefore, if he ever believed that it is permissible to judge between people by which he thinks just, then he is also a disbeliever.
Certainly, every Ummah (Nation) pretends to investigate the just way to judge between people. This way could be the outcome of their leaders’ diligence. In fact, many people who belong themselves to Islam judge by their ancestors’ traditions even if Allah has not decreed it. They think that their traditions should be applied in judgement neglecting the Book (Qur’an) and the Sunnah (Prophet’s Tradition), and this is certainly disbelief. If they ever knew that they should not judge except by what Allah has revealed and they insisted not to do, then they are disbelievers.” The Scholar Muhammad bin Ibrahim said, “as for a deeds which was said it is a minor disbelief when somebody judges by what Allah has not revealed, it is so when it is committed one time or so.
However, when someone adopted some rules other than Allah’s Revelation, then this is disbelief, even if they claimed to be mistaken. They would certainly be excluded from Islam by this murder.” Therefore, he differentiated between the partial non-repeated judgement, which once occurred by mistake, and the adopted general rules that are considered the reference for most or all of the legitimate aspects. This is verily considered disbelief excluding its people from Islam. This is because whosoever put the Shari’a (Allah’s Legislation) aside and preferred to resort to a substitute thinks surely that this substitute is better than Islamic Legislation, the deeds that is considered a major disbelief contradicting Tawhid (Islamic Monotheism).