Concise Quran Commentary
It is not befitting of the Merciful to take a son as He is pure of that.
وَمَا يَنۢبَغِى لِلرَّحْمَـٰنِ أَن يَتَّخِذَ وَلَدًا
It is not appropriate for the Most Compassionate to beget a son.
It is not befitting of the Merciful to take a son as He is pure of that.