وَمَا تَفَرَّقُوا إِلَّا مِنْ بَعْدِ مَا جَاءَهُمُ الْعِلْمُ بَغْيًا بَيْنَهُمْ وَلَوْلَا كَلِمَةٌ سَبَقَتْ مِنْ رَبِّكَ إِلَى أَجَلٍ مُسَمًّى لَقُضِيَ بَيْنَهُمْ وَإِنَّ الَّذِينَ أُورِثُوا الْكِتَابَ مِنْ بَعْدِهِمْ لَفِي شَكٍّ مِنْهُ مُرِيبٍ ﴿۱۴﴾ فَلِذَلِكَ فَادْعُ وَاسْتَقِمْ كَمَا أُمِرْتَ وَلَا تَتَّبِعْ أَهْوَاءَهُمْ وَقُلْ آمَنْتُ بِمَا أَنْزَلَ اللَّهُ مِنْ كِتَابٍ وَأُمِرْتُ لِأَعْدِلَ بَيْنَكُمُ اللَّهُ رَبُّنَا وَرَبُّكُمْ لَنَا أَعْمَالُنَا وَلَكُمْ أَعْمَالُكُمْ لَا حُجَّةَ بَيْنَنَا وَبَيْنَكُمُ اللَّهُ يَجْمَعُ بَيْنَنَا وَإِلَيْهِ الْمَصِيرُ ﴿۱۵﴾ وَالَّذِينَ يُحَاجُّونَ فِي اللَّهِ مِنْ بَعْدِ مَا اسْتُجِيبَ لَهُ حُجَّتُهُمْ دَاحِضَةٌ عِنْدَ رَبِّهِمْ وَعَلَيْهِمْ غَضَبٌ وَلَهُمْ عَذَابٌ شَدِيدٌ ﴿۱۶﴾

﴾14﴿ Wa maa tafarraqooo illaa mim ba'di maa jaaa'ahumul 'ilmu baghyam bainahum; wa law laa Kalimatun sabaqat mir Rabbika ilaaa ajalim musammal laqudiya bainahum; wa innal lazeena oorisul Kitaaba mim ba'dihim lafee shakkim minhu mureeb
﴾15﴿ Falizaalika fad'u wastaqim kamaaa umirta wa laa tattabi' ahwaaa'ahum wa qul aamantu bimaaa anzalal laahu min Kitaab, wa umirtu li a'dila bainakum Allaahu Rabbunaa wa Rabbukum lanaaa a'maa lunaa wa lakum a'maalukum laa hujjata bainanaa wa baina kumul laahu yajma'u bainanaa wa ilaihil maseer
﴾16﴿ Wallazeena yuhaaajjoona fil laahi mim ba'di mastujeeba lahoo hujjatuhum daahidatun 'inda Rabbihim wa 'alaihim ghadabunw wa lahum 'azaabun shadeed

﴾14﴿ And they did not become divided except after knowledge had come to them—out of mutual envy and rivalry among themselves. And if it were not for a preordained decree from your Lord for a specified term, the matter would have surely been settled between them. And indeed, those who were made to inherit the Scripture after them are in grave doubt concerning it
﴾15﴿ So for that reason, call them, and remain steadfast as you have been commanded, and do not follow their desires. And say, I have believed in whatever Allah has sent down of the Scripture, and I have been commanded to establish justice among you. Allah is our Lord and your Lord. For us are our deeds, and for you are your deeds. There is no argument between us and you. Allah will gather us together, and to Him is the final return
﴾16﴿ And those who dispute concerning the oneness of Allah after it has been accepted—their argument is futile in the sight of their Lord, and upon them is wrath, and for them is a severe punishment

[14] In this verse is the response to the third doubt, which is: “What kind of religion are you calling to, when so many scholars oppose it? Doesn’t that prove this religion is false?”
The essence of the answer is that the opposition of these scholars holds no weight, because their division and disagreement are based on a lack of true knowledge and evidence, and their opposition arises from enmity and stubbornness.
"Indeed, those who inherited the Book after them" (wa inna alladhīna ūrithū al-kitāba min ba‘dihim) — this refers to the common people and half-scholars, who are considered the heirs of the Book, but did not attain complete knowledge.
The conclusion is that the senior scholars, due to hatred and stubbornness, opposed Tawḥīd and the true religion, and wrote books supporting shirk.
Later, the half-scholars and the masses followed them blindly, imitated their books of shirk, and denied Tawḥīd.
[15] From this verse until verse 2 is the second section. In it, there is encouragement toward calling to the truth, presented in ten statements. Then comes a rebuke of those who oppose the call, and a call to them through the Qur’an, along with warning.
Then follows the third rational proof, accompanied by worldly threats, then a rebuke of shirk in legislation (taḥkīm), a warning and glad tidings, and a second rebuke — this time for denying the Messenger, along with an encouragement to repentance.
Then come three rational proofs, followed again by a worldly warning, and another rational argument.
In verse 15, there is encouragement to invite to the truth, and this is the remedy for preventing division, which was mentioned in the previous verse.
In this verse, ten instructions are given to the caller — these are the etiquettes of da‘wah (inviting to Allah):
"So to that, invite" (fa-li-dhālika fa’d‘u) — meaning, because of the need to prevent division and conflict, invite to the truth.
Or the "lām" here means "to" — and "that (dhālika)" refers to the religion of Tawḥīd mentioned in verse 13, or it refers to the Qur'an.
"Ahwā’ahum" — refers to matters without proof, created by scholars from themselves (i.e., innovations and false rulings).
"Say: I believe in what Allah has revealed" (wa qul āmantu bimā anzala Allāh) — meaning, when opponents use other books to justify shirk and innovation, you should respond: "I believe only in the Book that Allah has revealed."
[16] This is a consolation for the caller — that the arguments of your opponents are false and worthless, so do not pay attention to them.
"Istujība lahu" — means that the intelligent and aware people have accepted the call to the Tawḥīd of Allah the Exalted.
This itself is also a binding proof against the deniers.