Al-Ma'idah' - 5:48

وَأَنزَلْنَا إِلَيْكَ الْكِتَابَ بِالْحَقِّ مُصَدِّقًا لِّمَا بَيْنَ يَدَيْهِ مِنَ الْكِتَابِ وَمُهَيْمِنًا عَلَيْهِ فَاحْكُم بَيْنَهُم بِمَا أَنزَلَ اللّهُ وَلاَ تَتَّبِعْ أَهْوَاءهُمْ عَمَّا جَاءكَ مِنَ الْحَقِّ لِكُلٍّ جَعَلْنَا مِنكُمْ شِرْعَةً وَمِنْهَاجًا وَلَوْ شَاء اللّهُ لَجَعَلَكُمْ أُمَّةً وَاحِدَةً وَلَـكِن لِّيَبْلُوَكُمْ فِي مَا آتَاكُم فَاسْتَبِقُوا الخَيْرَاتِ إِلَى الله مَرْجِعُكُمْ جَمِيعًا فَيُنَبِّئُكُم بِمَا كُنتُمْ فِيهِ تَخْتَلِفُونَ
[5:48]
And We have revealed to you the Book with the truth, verifying what is before it of the Book and a guardian over it, therefore judge between them by what Allah has revealed, and do not follow their low desires (to turn away) from the truth that has come to you; for every one of you did We appoint a law and a way, and if Allah had pleased He would have made you (all) a single people, but that He might try you in what He gave you, therefore strive with one another to hasten to virtuous deeds; to Allah is your return, of all (of you), so He will let you know that in which you differed;
To thee We sent the Scripture in truth, confirming the scripture that came before it, and guarding it in safety: so judge between them by what Allah hath revealed, and follow not their vain desires, diverging from the Truth that hath come to thee. To each among you have we prescribed a law and an open way. If Allah had so willed, He would have made you a single people, but (His plan is) to test you in what He hath given you: so strive as in a race in all virtues. The goal of you all is to Allah; it is He that will show you the truth of the matters in which ye dispute;
And unto thee have We revealed the Scripture with the truth, confirming whatever Scripture was before it, and a watcher over it. So judge between them by that which Allah hath revealed, and follow not their desires away from the truth which hath come unto thee. For each We have appointed a divine law and a traced-out way. Had Allah willed He could have made you one community. But that He may try you by that which He hath given you (He hath made you as ye are). So vie one with another in good works. Unto Allah ye will all return, and He will then inform you of that wherein ye differ.