Volume 7 · Book 67 · Hadith 416
Narrates 'Abdullah bin Mughaffal: While we were besieging the castle of Khaibar, Somebody threw a skin full of fat and I went ahead to take it, but on looking behind, I saw the Prophet and I felt shy in his presence (and did not take it).
— Sahih Bukhari, Volume 7, Book 67: Hunting, Slaughtering, Hadith #416