Language:
كتاب الجنائز
23  
Funerals (Al-Janaa'iz)
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Chapter: What is said about funerals, and those whose last words were: La ilãha ilallãh (none has the right to be worshipped but Allah)
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باب فِي الْجَنَائِزِ وَمَنْ كَانَ آخِرُ كَلاَمِهِ لاَ إِلَهَ إِلاَّ اللَّهُ
Sahih al-Bukhari 1238

Narrated `Abdullah:

Allah's Messenger (ﷺ) said, "Anyone who dies worshipping others along with Allah will definitely enter the Fire." I said, "Anyone who dies worshipping none along with Allah will definitely enter Paradise."

حَدَّثَنَا عُمَرُ بْنُ حَفْصٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا الأَعْمَشُ، حَدَّثَنَا شَقِيقٌ، عَنْ عَبْدِ اللَّهِ ـ رضى الله عنه ـ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ مَنْ مَاتَ يُشْرِكُ بِاللَّهِ شَيْئًا دَخَلَ النَّارَ ‏"‏‏.‏ وَقُلْتُ أَنَا مَنْ مَاتَ لاَ يُشْرِكُ بِاللَّهِ شَيْئًا دَخَلَ الْجَنَّةَ‏.‏
Reference : Sahih al-Bukhari 1238
In-book reference : Book 23, Hadith 2
USC-MSA web (English) reference : Vol. 2, Book 23, Hadith 330
  (deprecated numbering scheme)