وَلَوْ شَاءَ اللَّهُ لَجَعَلَكُمْ أُمَّةً وَاحِدَةً وَلَٰكِن يُضِلُّ مَن يَشَاءُ وَيَهْدِي مَن يَشَاءُ ۚ وَلَتُسْأَلُنَّ عَمَّا كُنتُمْ تَعْمَلُونَ (93)
(16:93) Had Allah so willed (that you may not have any differences,) He would have made you all a single community, *93 but He leads astray whom He will and shows guidance to whom He will. *94 And be sure that He will take you to account for all your doings.
*93) This further supports the previous warning. It means that it would be wrong for any champion of Allah's religion to arrogate to himself the use of every sort of method and means irrespective of whether they are right or wrong to propagate his own religion (considering it to be Allah's Religion) and try to destroy opposite religions. For this would be utterly against the will of AIlah: if Allah had willed that there should be no religious differences, He could have deprived mankind of the freedom of choice. In that case, there would have been no need for Allah to get help of any such up-holder of His Religion, who uses disgraceful means for this purpose. Allah could have created all mankind to be inherent believers and obedient servants by depriving them of the power and option of disbelief and sin. Then there would have been none who could have dared to deviate from belief and obedience.
*94) This is to show that Allah Himself has given man the power and freedom to follow any out of the many ways. That is why Allah makes arrangements for the guidance of the one who intends to follow the right way, and lets go astray the one who desires to deviate.