Sunan Abi Dawud 4718
سنن أبي داود#4718Sahihحَدَّثَنَا مُوسَى بْنُ إِسْمَاعِيلَ، حَدَّثَنَا حَمَّادٌ، عَنْ ثَابِتٍ، عَنْ أَنَسٍ، أَنَّ رَجُلاً، قَالَ يَا رَسُولَ اللَّهِ أَيْنَ أَبِي قَالَ " أَبُوكَ فِي النَّارِ " . فَلَمَّا قَفَّى قَالَ " إِنَّ أَبِي وَأَبَاكَ فِي النَّارِ " .
Anas said :A man asked : where is my father, Messenger of Allah? He replied! Your father is in Hell. When he turned his back, he said : My father and your father are in Hell
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Zubair Ali ZaiSahih Muslim (203)
In-book reference: 42:123