The Messenger of Allah ﷺ said, "Whoever believes in Allah and the Last Day must not harm his neighbor. Whoever believes in Allah and the Last Day must honor his guest. And whoever believes in Allah and the Last Day must speak good or remain silent."
قال رسول الله ﷺ: من كان يؤمن بالله واليوم الآخر فلا يؤذ جاره، ومن كان يؤمن بالله واليوم الآخر فليكرم ضيفه، ومن كان يؤمن بالله واليوم الآخر فليقل خيرا أو ليصمت.
Bukhari narrated it in al-Adab (6018), and Muslim in al-Iman (47), both from the hadith of Abu Ahwas, from Abu Husayn, from Abu Salih, from Abu Hurairah, who related it. The wording given is that of Bukhari, and in Muslim's version it reads, "Let him say something good, or remain silent."