The Messenger of Allah ﷺ said, "Do not laugh excessively, for excessive laughter deadens the heart."
حدثنا بكر بن خلف حدثنا أبو بكر الحنفي حدثنا عبد الحميد بن جعفر عن إبراهيم بن عبد الله بن حنين
قال رسول الله ﷺ لا تكثروا الضحك فإن كثرة الضحك تميت القلب
[Its chain of transmission is hasan] Bukhari narrated it in Adab al-Mufrad, no. 253, from the hadith of Abu Bakr Hanafi, from Banu Hanifa, through this route, and Busiri graded it sahih. The hadith has supporting narrations in Tirmidhi, no. 2305, and elsewhere. See also no. 4217.