"And had Allah willed, He could have made them one community," meaning: upon faith. "But He admits whom He wills into His mercy," meaning: into His religion, which is Islam. "And the wrongdoers," meaning: the polytheists, "have no protector" to shield them from the punishment of Allah.
﴿وَلَوْ شَاء اللَّهُ لَجَعَلَهُمْ أُمَّةً وَاحِدَةً﴾ ﴿على الْإِيمَان﴾ (وَلَكِن يُدْخِلُ مَن يَشَاء فِي رَحْمَتِهِ﴾ يَعْنِي: فِي دينه؛ وَهُوَ الْإِسْلَام ﴿وَالظَّالِمُونَ﴾ ﴿الْمُشْركُونَ﴾ (مَا لَهُم مِّن وَلِيٍّ﴾ يمنعهُم (ل ٣١٠) من عَذَاب الله.