Sahih al-Bukhari · Hadith 3153

One-fifth of Booty to the Cause of Allah (Khumus)

Narrated `Abdullah bin Mughaffal: While we were besieging the fort of Khaibar, a person threw a leather container containing fat, and I ran to take it, but when I turned I saw the Prophet (standing behind), so I felt embarrassed in front of him