Abu Hurayra, may Allah be pleased with him, narrated that the Messenger of Allah, Sallallahu alaihi Wasallam, told me:
"O Abu Hurayra, be scrupulous and you will be the most devoted of people;
be content and you will be the most grateful of people; love for people what
you love for yourself and you will be a believer; be a good companion to those
in your company and you will be a Muslim; and decrease laughter, for truly, a
lot of laughter kills the heart." [Ibn Majah].