The Greatest Cause of Division: from a Quote by Ibn Taymiyyah

Shaykh Al-Islām Ibn Taymiyyah said in Darʾ Taʿārud Al-ʿAql wa Al-Naql (5/284):

And when they abandon adhering to the Qurʾān and the Sunnah, they will inevitably differ, because nothing can judge between people other than a Book sent down from the heavens, as Allāh the Almighty said:

﴿كَانَ ٱلنَّاسُ أُمَّةً وَٰحِدَةً فَبَعَثَ ٱللَّهُ ٱلنَّبِيِّـۧنَ مُبَشِّرِينَ وَمُنذِرِينَ وَأَنزَلَ مَعَهُمُ ٱلْكِتَـٰبَ بِٱلْحَقِّ لِيَحْكُمَ بَيْنَ ٱلنَّاسِ فِيمَا ٱخْتَلَفُوا۟ فِيهِ ۚ وَمَا ٱخْتَلَفَ فِيهِ إِلَّا ٱلَّذِينَ أُوتُوهُ مِنۢ بَعْدِ مَا جَآءَتْهُمُ ٱلْبَيِّنَـٰتُ بَغْيًۢا بَيْنَهُمْ ۖ فَهَدَى ٱللَّهُ ٱلَّذِينَ ءَامَنُوا۟ لِمَا ٱخْتَلَفُوا۟ فِيهِ مِنَ ٱلْحَقِّ بِإِذْنِهِۦ ۗ وَٱللَّهُ يَهْدِى مَن يَشَآءُ إِلَىٰ صِرَٰطٍ مُّسْتَقِيمٍ ﴿٢١٣﴾ ﴾

Mankind was [of] one religion [before their deviation]; then Allāh sent the prophets as bringers of good tidings and warners and sent down with them the Scripture in truth to judge between the people concerning that in which they differed. And none differed over it [i.e., the Scripture] except those who were given it - after the clear proofs came to them - out of jealous animosity among themselves. And Allāh guided those who believed to the truth concerning that over which they had differed, by His permission. And Allāh guides whom He wills to a straight path.

And Allāh the Almighty said:

﴿يَـٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوٓا۟ أَطِيعُوا۟ ٱللَّهَ وَأَطِيعُوا۟ ٱلرَّسُولَ وَأُو۟لِى ٱلْأَمْرِ مِنكُمْ ۖ فَإِن تَنَـٰزَعْتُمْ فِى شَىْءٍ فَرُدُّوهُ إِلَى ٱللَّهِ وَٱلرَّسُولِ إِن كُنتُمْ تُؤْمِنُونَ بِٱللَّهِ وَٱلْيَوْمِ ٱلْـَٔاخِرِ ۚ ذَٰلِكَ خَيْرٌ وَأَحْسَنُ تَأْوِيلًا ﴿٥٩﴾ ﴾

O you who have believed, obey Allāh and obey the Messenger and those in authority among you. And if you disagree over anything, refer it to Allāh and the Messenger, if you should believe in Allāh and the Last Day. That is the best and fairest resolution.

And Allāh the Almighty said:

﴿يَـٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ ٱتَّقُوا۟ ٱللَّهَ حَقَّ تُقَاتِهِۦ وَلَا تَمُوتُنَّ إِلَّا وَأَنتُم مُّسْلِمُونَ ﴿١٠٢﴾ وَٱعْتَصِمُوا۟ بِحَبْلِ ٱللَّهِ جَمِيعًا وَلَا تَفَرَّقُوا۟ ۚ وَٱذْكُرُوا۟ نِعْمَتَ ٱللَّهِ عَلَيْكُمْ إِذْ كُنتُمْ أَعْدَآءً فَأَلَّفَ بَيْنَ قُلُوبِكُمْ فَأَصْبَحْتُم بِنِعْمَتِهِۦٓ إِخْوَٰنًا وَكُنتُمْ عَلَىٰ شَفَا حُفْرَةٍ مِّنَ ٱلنَّارِ فَأَنقَذَكُم مِّنْهَا ﴾

‘O you who have believed, fear Allāh as He should be feared and do not die except as Muslims [in submission to Him]. And hold firmly to the rope of Allāh all together and do not become divided. And remember the favor of Allāh upon you - when you were enemies and He brought your hearts together and you became, by His favor, brothers. And you were on the edge of a pit of the Fire, and He saved you from it.

There is no unity except by learning the Qurʾān and the Sunnah according to the understanding of the pious predecessors of the Ummah, since the Ummah does not unite on misguidance, and innovations are misguidance. Therefore, there is no unity except by eliminating innovations.

So the ramblings of the ḥizbīs (i.e. partisans for a group rather than Islām) concerning the uniting the Ummah and forgetting differences – which in reality is abandoning loyalty and disavowal based on correct belief – is nothing but a myth, since there is no unity except by holding fast to the Qurʾān and the Sunnah.

Whoever seeks to unite in something other than that will be rewarded with the opposite of what he intended, and his innovation becomes a cause of division, enmity and hatred. Allāh the Almighty said:

﴿وَمِنَ ٱلَّذِينَ قَالُوٓا۟ إِنَّا نَصَـٰرَىٰٓ أَخَذْنَا مِيثَـٰقَهُمْ فَنَسُوا۟ حَظًّا مِّمَّا ذُكِّرُوا۟ بِهِۦ فَأَغْرَيْنَا بَيْنَهُمُ ٱلْعَدَاوَةَ وَٱلْبَغْضَآءَ إِلَىٰ يَوْمِ ٱلْقِيَـٰمَةِ ۚ وَسَوْفَ يُنَبِّئُهُمُ ٱللَّهُ بِمَا كَانُوا۟ يَصْنَعُونَ ﴿١٤﴾ ﴾

And from those who say, "We are Christians" We took their covenant; but they forgot a portion of that of which they were reminded. So We caused among them animosity and hatred until the Day of Resurrection. And Allāh is going to inform them about what they used to do.