Firqa (Division in Umma) is Shirk in Holy Quran:
(sūrat l-rūm)Verse (30:31-32): مُنِيبِينَ إِلَيۡهِ وَٱتَّقُوهُ وَأَقِيمُواْ ٱلصَّلَوٰةَ وَلَا تَكُونُواْ مِنَ ٱلۡمُشۡرِڪِينَ (٣١)
مِنَ ٱلَّذِينَ فَرَّقُواْ دِينَهُمۡ وَڪَانُواْ شِيَعً۬اۖ كُلُّ حِزۡبِۭ بِمَا لَدَيۡہِمۡ فَرِحُونَ
Sahih International: [Adhere to it], turning in repentance to Him, and fear Him and establish prayer and do not be of those who associate others with Allah.[Or] of those who have divided their religion and become sects, every faction rejoicing in what it has.
(sūrat l-anʿām)Verse (6:159): إِنَّ ٱلَّذِينَ فَرَّقُواْ دِينَہُمۡ وَكَانُواْ شِيَعً۬ا لَّسۡتَ مِنۡہُمۡ فِى شَىۡءٍۚ إِنَّمَآ أَمۡرُهُمۡ إِلَى ٱللَّهِ ثُمَّ يُنَبِّئُہُم بِمَا كَانُواْ يَفۡعَلُونَ
Sahih International: Indeed, those who have divided their religion and become sects – you, [O Muhammad], are not [associated] with them in anything. Their affair is only [left] to Allah ; then He will inform them about what they used to do.
(sūrat āl ʿim’rān)Verse (3:103): وَٱعۡتَصِمُواْ بِحَبۡلِ ٱللَّهِ جَمِيعً۬ا وَلَا تَفَرَّقُواْۚ وَٱذۡكُرُواْ نِعۡمَتَ ٱللَّهِ عَلَيۡكُمۡ إِذۡ كُنتُمۡ أَعۡدَآءً۬ فَأَلَّفَ بَيۡنَ قُلُوبِكُمۡ فَأَصۡبَحۡتُم بِنِعۡمَتِهِۦۤ إِخۡوَٲنً۬ا وَكُنتُمۡ عَلَىٰ شَفَا حُفۡرَةٍ۬ مِّنَ ٱلنَّارِ فَأَنقَذَكُم مِّنۡہَاۗ كَذَٲلِكَ يُبَيِّنُ ٱللَّهُ لَكُمۡ ءَايَـٰتِهِۦ لَعَلَّكُمۡ تَہۡتَدُونَ
Sahih International: And hold firmly to the rope of Allah all together and do not become divided. And remember the favor of Allah 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. Thus does Allah make clear to you His verses that you may be guided.
A clear message from Allah:
Whoever splits His religion (دِينَهُمۡ) and divides the Ummah into parties or groups (شِيَعً۬اۖ) is a Mushrik. Why is this considered shirk? Because no one, other than Allah, has the right or authority to alter or make changes to His religion (دِينَهُمۡ). This is the sole right of Allah Himself. Anyone who attempts to do so is arrogantly claiming to share in Allah’s exclusive authority. This rule applies to every Muslim sect without exception.
It may be very hard and challenging to follow it, but it is the command of the Almighty Quran. We must adjust ourselves to its rules, rather than attempting to manipulate its meanings to justify our wrong behavior.
Do not stand [for prayer] within it – ever. Even in a Mosque that make division among the believers:
(sūrat l-tawbah)Verse (9:107): وَٱلَّذِينَ ٱتَّخَذُواْ مَسۡجِدً۬ا ضِرَارً۬ا وَڪُفۡرً۬ا وَتَفۡرِيقَۢا بَيۡنَ ٱلۡمُؤۡمِنِينَ وَإِرۡصَادً۬ا لِّمَنۡ حَارَبَ ٱللَّهَ وَرَسُولَهُ ۥ مِن قَبۡلُۚ وَلَيَحۡلِفُنَّ إِنۡ أَرَدۡنَآ إِلَّا ٱلۡحُسۡنَىٰۖ وَٱللَّهُ يَشۡہَدُ إِنَّہُمۡ لَكَـٰذِبُونَ (١٠٧) لَا تَقُمۡ فِيهِ أَبَدً۬اۚ لَّمَسۡجِدٌ أُسِّسَ عَلَى ٱلتَّقۡوَىٰ مِنۡ أَوَّلِ يَوۡمٍ أَحَقُّ أَن تَقُومَ فِيهِۚ فِيهِ رِجَالٌ۬ يُحِبُّونَ أَن يَتَطَهَّرُواْۚ وَٱللَّهُ يُحِبُّ ٱلۡمُطَّهِّرِينَ
Sahih International: And [there are] those [hypocrites] who took for themselves a mosque for causing harm and disbelief and division among the believers and as a station for whoever had warred against Allah and His Messenger before. And they will surely swear, “We intended only the best.” And Allah testifies that indeed they are liars. Do not stand [for prayer] within it – ever. A mosque founded on righteousness from the first day is more worthy for you to stand in. Within it are men who love to purify themselves; and Allah loves those who purify themselves.
Even a great Prophet showed temporary tolerance for the worship of the calf to avoid “تَفَرَّقَ“
“Division among the Children of Israel”.
(sūrat ṭā hā)Verse (20:94): قَالَ يَبۡنَؤُمَّ لَا تَأۡخُذۡ بِلِحۡيَتِى وَلَا بِرَأۡسِىٓۖ إِنِّى خَشِيتُ أَن تَقُولَ فَرَّقۡتَ بَيۡنَ بَنِىٓ إِسۡرَٲٓءِيلَ وَلَمۡ تَرۡقُبۡ قَوۡلِى
Sahih International: [Aaron] said, “O son of my mother, do not seize [me] by my beard or by my head. Indeed, I feared that you would say, ‘You caused division among the Children of Israel, and you did not observe [or await] my word.’ “
…Continued…