ٱدْعُوهُمْ لِـَٔابَآئِهِمْ هُوَ أَقْسَطُ عِندَ ٱللَّهِ ۚ فَإِن لَّمْ تَعْلَمُوٓا۟ ءَابَآءَهُمْ فَإِخْوَٰنُكُمْ فِى ٱلدِّينِ وَمَوَٰلِيكُمْ ۚ وَلَيْسَ عَلَيْكُمْ جُنَاحٌ فِيمَآ أَخْطَأْتُم بِهِۦ وَلَـٰكِن مَّا تَعَمَّدَتْ قُلُوبُكُمْ ۚ وَكَانَ ٱللَّهُ غَفُورًا رَّحِيمًا
Ud'oohum li aabaaa'ihim huwa aqsatu 'indal laah; fa illam ta'lamooo aabaaa'ahum fa ikhwaanukum fid deeni wa mawaaleekum; wa laisa 'alaikum junaahun feemaaa akhtaatum bihee wa laakim maa ta'ammadat quloobukum; wa kaanal laahu Ghafoorar Raheemaa
Name your adopted sons after their real fathers: this is more equitable in God’s eyes––if you do not know who their fathers are [they are your] ‘brothers-in-religion’ and proteges. You will not be blamed if you make a mistake, only for what your hearts deliberately intend; God is most forgiving and merciful.
Call them by their fathers' names — that is more just in God's sight. And if you do not know their fathers, then they are your brothers in faith and your kin. There is no blame on you for what you do by mistake, only for what your hearts have intended. And God is ever forgiving, merciful.