Sahih al-Bukhari 1384
Book 23: Funerals (Al-Janaa'iz) · Narrated by Abu Huraira
Arabic
حَدَّثَنَا أَبُو الْيَمَانِ، أَخْبَرَنَا شُعَيْبٌ، عَنِ الزُّهْرِيِّ، قَالَ أَخْبَرَنِي عَطَاءُ بْنُ يَزِيدَ اللَّيْثِيُّ، أَنَّهُ سَمِعَ أَبَا هُرَيْرَةَ ـ رضى الله عنه ـ يَقُولُ سُئِلَ النَّبِيُّ صلى الله عليه وسلم عَنْ ذَرَارِيِّ الْمُشْرِكِينَ فَقَالَ " اللَّهُ أَعْلَمُ بِمَا كَانُوا عَامِلِينَ ".
English translation
Narrated Abu Huraira:The Prophet (ﷺ) was asked about the offspring of pagans (Mushrikeen); so he said, "Allah knows what sort of deeds they would have done
Reference: Sahih al-Bukhari 1384, Book of Funerals (Al-Janaa'iz). English translation by Dr. Muhammad Muhsin Khan.