In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
Allaah [The Most High] said: [ وَمَآ أَرۡسَلۡنَا مِن رَّسُولٍ إِلَّا لِيُطَاعَ بِإِذۡنِ ٱللَّهِۚ – We sent no Messenger, but to be obeyed by Allah’s Leave] [Surah An-Nisaa’ Ayah 64]
Allaah [The Most High] commanded and urged us to obey the Messenger and willingly submit to his path. He [The Most High] informed us that the purpose behind sending the Messengers is so that they are obeyed [and followed] in everything they command and keep away from everything they prohibited. This shows us that the Messengers are infallible in that which they convey from Allaah, command and prohibit, because Allaah commanded us to follow them unconditionally. Had it not been that they were infallible in that which they convey from Allaah’s and the fact that they never legislate anything [by themselves], then Allaah would not have commanded us to obey them unconditionally.
Also, Allaah [The Most High] said in Surah An-Nisaa Ayah 65: [ فَلَا وَرَبِّكَ لَا يُؤۡمِنُونَ حَتَّىٰ يُحَكِّمُوكَ فِيمَا شَجَرَ بَيۡنَهُمۡ ثُمَّ لَا يَجِدُواْ فِىٓ أَنفُسِہِمۡ حَرَجً۬ا مِّمَّا قَضَيۡتَ وَيُسَلِّمُواْ تَسۡلِيمً۬ا – But no, by your Lord, they can have no Faith, until they make you (O Muhammad ) judge in all disputes between them, and find in themselves no resistance against your decisions, and accept (them) with full submission].
The people can never be true believers until they accept the judgements of Allaah’s Messenger in their disputes – in every affair about which they differ- except the issues of Ijmaa; because Ijmaa does not take place except based on evidence in the Qur’aan and authentic Sunnah. And it is not enough that people merely [and only] accept the judgements of the Messenger in that which they differ amongst themselves, rather there cannot be any resistance and reservation in their hearts after that judgement. It is not enough to merely demonstrate one’s acceptance; rather one has to submit wholeheartedly and willingly with a heart filled with ease about that judgement – in private and public.
Therefore, judging by what Islam has commanded without harbouring any reservations is a proof of one’s Eemaan-a proof of one’s obedience in fulfilling perfectly what he has been commanded and keeping away from what He has been forbidden. And whoever perfects these affairs, then indeed he has perfected all affairs related to his practice of the religion. And whoever abandons the Messenger’s judgement by not believing that it is the judgement that should be to be established, then he is an unbeliever. [Ref 1] As for the one who abandons it, but firmly believes that it is truth, then the judgement passed on him is similar to the one passed against the sinners who have not left the fold of Islaam.
[Source:(Tayseer al-Kareem Ar-Rahmaan Fee Tafseer Kalaam al-Mannaan). Slightly paraphrased]
[Ref 1: NB: Takfeer is not an affair that is left to the common Muslims, the students of knowledge or the misguided Takfeeris; rather it is the responsibility of the rightly guided scholars of Ahlus Sunnah.
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