Sahih Bukhari Volume 2, Book 23, Hadith 1313

حَدَّثَنَا آدَمُ، حَدَّثَنَا شُعْبَةُ، حَدَّثَنَا عَمْرُو بْنُ مُرَّةَ، قَالَ سَمِعْتُ عَبْدَ الرَّحْمَنِ بْنَ أَبِي لَيْلَى، قَالَ كَانَ سَهْلُ بْنُ حُنَيْفٍ وَقَيْسُ بْنُ سَعْدٍ قَاعِدَيْنِ بِالْقَادِسِيَّةِ، فَمَرُّوا عَلَيْهِمَا بِجَنَازَةٍ فَقَامَا‏.‏ فَقِيلَ لَهُمَا إِنَّهَا مِنْ أَهْلِ الأَرْضِ، أَىْ مِنْ أَهْلِ الذِّمَّةِ فَقَالاَ إِنَّ النَّبِيَّ صلى الله عليه وسلم مَرَّتْ بِهِ جَنَازَةٌ فَقَامَ فَقِيلَ لَهُ إِنَّهَا جَنَازَةُ يَهُودِيٍّ‏.‏ فَقَالَ ‏"‏ أَلَيْسَتْ نَفْسًا ‏"

Narrated By 'Abdur Rahman bin Abi Laila : Sahl bin Hunaif and Qais bin Sad were sitting in the city of Al-Qadisiya. A funeral procession passed in front of them and they stood up. They were told that funeral procession was of one of the inhabitants of the land i.e. of a non-believer, under the protection of Muslims. They said, "A funeral procession passed in front of the Prophet and he stood up. When he was told that it was the coffin of a Jew, he said, "Is it not a living being (soul)?"