Jami` at-Tirmidhi 2319

Muhammed bin 'Amr narrated from his father, from his grandfather who said:"I heard Bilal bin Al-Harith Al Muzani, the Companion of the Messenger of Allah (s.a.w) saying: 'I heard the Messenger of Allah (s.a.w) saying: "Indeed one of you says a statement pleasing to Allah, not realizing that you have achieved what you have achieved. Then for it, Allah writes for him His pleasure until the Day of Meeting Him. And one of you says a statement angering Allah, not realizing that you have achieved what you have achieved. Then for it, Allah writes for him His anger until the Day of Meeting with Him