Hadith 4451
أَخْبَرَنَا يُوسُفُ بْنُ عِيسَى، قَالَ أَنْبَأَنَا الْفَضْلُ بْنُ مُوسَى، قَالَ أَنْبَأَنَا الأَعْمَشُ، عَنْ إِبْرَاهِيمَ، عَنِ الأَسْوَدِ، عَنْ عَائِشَةَ، قَالَتْ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " إِنَّ أَطْيَبَ مَا أَكَلَ الرَّجُلُ مِنْ كَسْبِهِ وَوَلَدُهُ مِنْ كَسْبِهِ " .
It was narrated that 'Aishah said:
"The Messenger of Allah said: 'The best (most pure) food that a man eats is that which he has earned himself, and his child (and his child's wealth) is part of his earning,"
Reference : Sunan an-Nasa'i 4451
In-book reference : Book 44, Hadith 3