The Book of the Believer · Hadith 133 (#Ḥadīth #27)
Chapter 5 | The Reward of Helping a Believer, Relieving Him of Distress And Showing Him Kindness
133- وعن أبي جعفر عليه السلام قال: ما [من] عمل يعمله المسلم أحب إلى الله عز وجل من إدخال السرور على أخيه المسلم، وما من رجل يدخل على أخيه المسلم بابا من السرور إلا أدخل الله عز وجل عليه بابا من السرور
133. It has been reported that Abu Ja'far said: No action of a Muslim is more loved by Allah than bringing joy to his Muslim brother; and anyone who brings joy to his Muslim brother, Allah will bring an equal measure of joy to him.
Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).