Language:
كتاب فرض الخمس
57  
One-fifth of Booty to the Cause of Allah (Khumus)
(7)
Chapter: The Statement of Allah Taa'la: "Verily one-fifth of it is assigned to Allah and to the Messenger saws ..."
(7)
بَابُ قَوْلِ اللَّهِ تَعَالَى: {فَأَنَّ لِلَّهِ خُمُسَهُ}
Sahih al-Bukhari 3116
Narrated Muawiya:

Allah's Messenger (ﷺ) said, "If Allah wants to do good for somebody, he makes him comprehend the Religion (i.e. Islam), and Allah is the Giver and I am Al-Qasim (i.e. the distributor), and this (Muslim) nation will remain victorious over their opponents, till Allah's Order comes and they will still be victorious."

حَدَّثَنَا حِبَّانُ، أَخْبَرَنَا عَبْدُ اللَّهِ، عَنْ يُونُسَ، عَنِ الزُّهْرِيِّ، عَنْ حُمَيْدِ بْنِ عَبْدِ الرَّحْمَنِ، أَنَّهُ سَمِعَ مُعَاوِيَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ مَنْ يُرِدِ اللَّهُ بِهِ خَيْرًا يُفَقِّهْهُ فِي الدِّينِ، وَاللَّهُ الْمُعْطِي وَأَنَا الْقَاسِمُ، وَلاَ تَزَالُ هَذِهِ الأُمَّةُ ظَاهِرِينَ عَلَى مَنْ خَالَفَهُمْ حَتَّى يَأْتِيَ أَمْرُ اللَّهِ وَهُمْ ظَاهِرُونَ ‏"‏‏.‏
Reference : Sahih al-Bukhari 3116
In-book reference : Book 57, Hadith 25
USC-MSA web (English) reference : Vol. 4, Book 53, Hadith 346
  (deprecated numbering scheme)