The Book Pertaining to the Excellent Qualities of the Holy Prophet (may Peace be upon them) and His Companions (Kitab Al-Fada'il)
Muslim :: Book 30 : Hadith 5718
Ibn 'Abbas reported that Allah's Messenger (may peace be upon him) was the most generous of people in charity, but he was generous to the utmost in the month of Ramadan. Gabriel (peace be upon him) would meet him every year during the month of Ramadin until it ended, and Allah's Messenger (may peace be upon him) recited to him the Qur'an; and when Gabriel met him Allah's Messenger (may peace be upon him) was most generous in giving charity like the blowing wind.