It was narrated that Abu Sa'eed Al-Khudri said:
"The Messenger of Allah said: 'Allah smiles at three things: a row in the prayer, a man who prays in the depths of the night, and a man who fights' I think he said, 'behind the battalion.'" (DE)
English reference (DE): Vol. 1, Book 1, Hadith 200 (DE)
Arabic reference (DE): Book 1, Hadith 205 (DE)