The Messenger of Allah ﷺ said, "Modesty is part of faith, and faith leads to Paradise. Foul speech is part of harshness, and harshness leads to the Fire."
قال رسول الله ﷺ: الحياء من الإيمان، والإيمان في الجنة، والبذاء من الجفاء، والجفاء في النار.
Tirmidhi (2009) narrated it through several routes from Muhammad bin Amr, who said, Abu Salama narrated to us, from Abu Hurairah, and he related it. Tirmidhi said, "Hasan sahih." Ibn Hibban (608) and Hakim (1/52-53) both graded it sahih, each through this route, and Hakim said, "Sahih according to the criterion of Muslim."I say, it contains Muhammad bin Amr, and although he is among the narrators found in the six major collections, there is disagreement about him, and his hadith is hasan. Saeed bin Abu Hilal corroborated him, narrating from Abu Salama bin Abdul-Rahman. Ibn Hibban (609) narrated it through this route, so the hadith becomes sahih.