بسم الله الرحمن الرحيم
Assalamu Alaikum.
إن أحدكم ليتكلم بالكلمة من رضوان الله ما يظن أن تبلغ ما بلغت فيكتب الله له بها رضوانه إلى يوم يلقاه ، وإن أحدكم ليتكلم بالكلمة من سخط الله ما يظن أن تبلغ ما بلغت فيكتب الله عليه بها سخطه إلى يوم يلقاه
The Messenger of Allah (salallahu alaihi wasallam) said: “Indeed one of you says a statement pleasing to Allah, not realising 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 realising that you have achieved what you have achieved. Then for it, Allah writes for him His Anger until the Day of meeting Him.” [Sunan At-Tirmidhi, Hadeeth No. 2319. Graded "sahih" by Shaikh Al-Albani in Sahih Sunan At-Tirmidhi, Hadeeth No. 2319]