It has been narrated on the authority of Abdullah b. Mughaffal who said I found a bag containing fat on the day of the Battle of Khaibar. I caught hold of it and said
I will not give anything today from it to anybody. Then I turned round and saw that the Messenger of Allah (ﷺ) was smiling (at my words).
This tradition has been transmitted by a different chain of narrators with a different wording, the last in the chain being the same narrator, (i. e. 'Abdullah b. Mughaffal), who said
A bag containing food and fat was thrown to us. I lept forward to catch it. Then I turned round and saw (to my surprise) the Messenger of Allah (ﷺ) and I felt ashamed of my act in his presence.
This hadith has been transmitted on the authority of Shu'ba with a slight variation of words.