Quran 33, Al-Ahzab (Confederates)

33:4 Allah has not made for a man two hearts in his interior. And He has not made your wives whom you declare unlawful your mothers. And he has not made your adopted sons your [true] sons. That is [merely] your saying by your mouths, but Allah says the truth, and He guides to the [right] way.

مَا جَعَلَ اللَّهُ لِرَجُلٍ مِنْ قَلْبَيْنِ فِي جَوْفِهِ وَمَا جَعَلَ أَزْوَاجَكُمُ اللَّائِي تُظَاهِرُونَ مِنْهُنَّ أُمَّهَاتِكُمْ وَمَا جَعَلَ أَدْعِيَاءَكُمْ أَبْنَاءَكُمْ ذَلِكُمْ قَوْلُكُمْ بِأَفْوَاهِكُمْ وَاللَّهُ يَقُولُ الْحَقَّ وَهُوَ يَهْدِي السَّبِيلَ